CN114364761A

CN114364761A - Adhesive tape for semiconductor processing

Info

Publication number: CN114364761A
Application number: CN202080021280.8A
Authority: CN
Inventors: 土屋贵德; 石黑邦彦
Original assignee: Furukawa Electric Co Ltd
Current assignee: Furukawa Electric Co Ltd
Priority date: 2020-07-30
Filing date: 2020-11-24
Publication date: 2022-04-15
Anticipated expiration: 2040-11-24
Also published as: WO2022024408A1; JPWO2022024408A1; JP7008164B1; CN114364761B; KR102535064B1; KR20220016019A; TWI793509B; TW202204553A

Abstract

Provided is a semiconductor processing tape which can easily peel a chip with an adhesive layer from the adhesive layer at the time of picking up, can reliably adhere a fixing ring frame, and does not generate the floating of the adhesive layer at the time of bonding a semiconductor wafer. The adhesive tape (1) for semiconductor processing is characterized in that a base material film (41), a first adhesive layer (42) and a second adhesive layer (43) are sequentially arranged, an adhesive layer (3) is arranged on the surface of the second adhesive layer (43) opposite to the base material film (41) and the first adhesive layer (42), the adhesive force of the first adhesive layer (42) is larger than that of the second adhesive layer (43), the first adhesive layer (42), the second adhesive layer (43) and the adhesive layer (3) respectively have a planar shape, the planar shape of the adhesive layer (3) is larger than that of the second adhesive layer (43), the planar shape of the first adhesive layer (42) is larger than that of the adhesive layer (3), the first pressure-sensitive adhesive layer (42) is in contact with the adhesive layer (3) at the peripheral portion of the second pressure-sensitive adhesive layer (43).

Description

Adhesive tape for semiconductor processing

Technical Field

The present invention relates to an adhesive tape having an adhesive layer on a base film, and a semiconductor processing tape having an adhesive layer on the adhesive layer to be bonded to a semiconductor wafer.

Background

Conventionally, in a manufacturing process of a semiconductor device, an adhesive tape for holding a semiconductor wafer by adhesion is used in a dicing process of dicing the semiconductor wafer into individual pieces. In order to simplify the process, a semiconductor processing tape has been proposed in which an adhesive layer for fixing a chip, which is required for a mounting process, is integrated (see, for example, patent document 1).

After the semiconductor wafer is diced in the dicing step, the diced chips are picked up by being pushed up via a push-up pin in the pick-up step with the adhesive layer being peeled off from the adhesive layer, and are directly bonded to a lead frame, a package substrate, or the like in the mounting step.

In recent years, with the spread of IC cards, thinning of semiconductor chips has been desired. Therefore, it is necessary to reduce the thickness of a conventional semiconductor chip having a thickness of about 350 μm to 50 to 100 μm or less. Further, the increase in chip size due to the pursuit of high integration is also advancing.

The thin semiconductor chip is broken when the push-up height of the push-up pin is increased at the time of pick-up, and thus the push-up height needs to be decreased. As a result, the adhesive force of the adhesive layer needs to be lowered in order to peel the semiconductor chip with the adhesive layer from the adhesive layer. In addition, since a large-sized semiconductor chip has a large contact area with the pressure-sensitive adhesive layer, the adhesive force of the pressure-sensitive adhesive layer still needs to be lowered in order to peel the semiconductor chip with the pressure-sensitive adhesive layer from the pressure-sensitive adhesive layer.

However, a ring frame for holding the semiconductor wafer on the dicing device or the pickup device is also bonded to the adhesive layer. As described above, when the adhesive force of the adhesive layer is reduced, the ring frame may be peeled off from the adhesive layer. In particular, the semiconductor wafer and the ring frame may be stored while being bonded to the semiconductor processing tape for a certain period of time, and in this case, the ring frame is likely to be peeled off from the adhesive layer.

In order to solve the above-described problems, a dicing die-bonding film is disclosed in which an ultraviolet-curable adhesive layer is cured in advance in accordance with the size of the adhesive layer to reduce the adhesive force, whereby a die with the adhesive layer can be easily peeled off from the adhesive layer at the time of picking up, and a fixing ring frame can be reliably bonded to a portion of the adhesive layer where the adhesive force is large without being irradiated with ultraviolet light (see, for example, patent document 2).

Further, there is disclosed a dicing tape-integrated film for semiconductor back surface having a dicing tape in which a base material layer, a1 st adhesive layer and a2 nd adhesive layer are sequentially laminated, and a film for semiconductor back surface laminated on the 2 nd adhesive layer of the dicing tape, wherein the peel strength Y between the 1 st adhesive layer and the 2 nd adhesive layer is 0.2 to 10N/20mm, and the peel strength X between the 2 nd adhesive layer and the film for semiconductor back surface is 0.01 to 0.2N/20mm (for example, see patent document 3).

In the dicing tape-integrated film for semiconductor back surface, the peel strength X is set to 0.01 to 0.2N/20mm, so that the holding force during dicing can be sufficiently ensured, the film for semiconductor back surface can be prevented from turning up during dicing, contamination of semiconductor chips can be effectively prevented, and the peeling easiness during picking up can be improved.

In addition, in the dicing tape-integrated film for semiconductor back surface, the peel strength Y is set to 0.2 to 10N/20mm, so that the adhesion to the ring frame during dicing can be improved, the holding force of the semiconductor wafer can be sufficiently ensured, and the transfer (adhesive residue) of the adhesive of the 2 nd adhesive layer to the film for semiconductor back surface due to the peeling between the 1 st adhesive layer and the 2 nd adhesive layer can be prevented.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open No. 2008 and 218571

Patent document 2: japanese patent No. 4717085

Patent document 3: japanese laid-open patent publication No. 2012-33637

Disclosure of Invention

However, in the dicing die-bonding film of patent document 2, it is difficult to accurately irradiate ultraviolet light only in a desired range of the pressure-sensitive adhesive layer, and therefore, in order to realize such a dicing die-bonding film, there is a problem that the process becomes complicated such as applying a shield to a portion other than the desired range.

In the dicing tape-integrated film for semiconductor back surface of patent document 3, the 2 nd adhesive layer is formed in a portion larger than a portion corresponding to the bonded portion of the film for semiconductor back surface and smaller than the entire surface of the 1 st adhesive layer, or the 2 nd adhesive layer is formed only in a portion corresponding to the bonded portion of the film for semiconductor back surface. Therefore, in the step of bonding the dicing tape-integrated semiconductor back surface film to the semiconductor wafer, when the release film covering the surface on the adhesive layer side of the dicing tape-integrated semiconductor back surface film is peeled off or when tension is applied to the dicing tape-integrated semiconductor back surface film via a bonding apparatus, the 2 nd adhesive layer having a low peeling force is partially peeled off from the semiconductor back surface film, the adhesive layer floats, and the bonding is performed in a state where the adhesive layer is wrinkled when the semiconductor wafer is bonded.

Accordingly, an object of the present invention is to provide a semiconductor processing tape which can easily peel a chip with an adhesive layer from the adhesive layer at the time of picking up, can reliably adhere a fixing ring frame, and does not cause the adhesive layer to float at the time of bonding to a semiconductor wafer.

Means for solving the problems

In order to solve the above problems, a tape for semiconductor processing according to the present invention is characterized in that a base film, a first pressure-sensitive adhesive layer, and a second pressure-sensitive adhesive layer are provided in this order, an adhesive layer is provided on a surface of the second pressure-sensitive adhesive layer opposite to the base film and the first pressure-sensitive adhesive layer, the adhesive strength of the first pressure-sensitive adhesive layer is higher than the adhesive strength of the second pressure-sensitive adhesive layer, each of the first pressure-sensitive adhesive layer, the second pressure-sensitive adhesive layer, and the adhesive layer has a planar shape, the planar shape of the adhesive layer is higher than the planar shape of the second pressure-sensitive adhesive layer, the planar shape of the first pressure-sensitive adhesive layer is higher than the planar shape of the adhesive layer, and the first pressure-sensitive adhesive layer and the adhesive layer are in contact with each other in a peripheral portion of the second pressure-sensitive adhesive layer.

In the semiconductor processing tape, the adhesive force between the second adhesive layer and the SUS304 surface is preferably 0.1-0.6N/25 mm under the conditions of 23 ℃ and 50% RH, a peeling angle of 180 degrees and a peeling speed of 300 mm/min.

In the semiconductor processing tape, the adhesive force between the first pressure-sensitive adhesive layer and the SUS304 surface is preferably 1 to 10N/25mm under the conditions of 23 ℃ and 50% RH, a peeling angle of 180 degrees, and a peeling speed of 300 mm/min.

In the semiconductor processing tape, the first pressure-sensitive adhesive layer is preferably a radiation non-curable type that is not cured by irradiation with radiation.

In the semiconductor processing tape, the second pressure-sensitive adhesive layer is preferably a radiation non-curable type that is not cured by irradiation with radiation.

In the semiconductor processing tape, the planar shape of the second pressure-sensitive adhesive layer is preferably larger than that of the semiconductor wafer bonded to the pressure-sensitive adhesive layer.

Effects of the invention

According to the present invention, it is possible to provide a semiconductor processing tape that can easily peel a chip with an adhesive layer from the adhesive layer at the time of picking up, can reliably adhere a fixing ring frame, and does not cause the adhesive layer to float at the time of bonding a semiconductor wafer.

Drawings

Fig. 1 is a sectional view schematically showing the structure of a semiconductor processing tape according to an embodiment of the present invention.

Fig. 2(a) is a plan view schematically showing the structure of the semiconductor processing tape according to the embodiment of the present invention, and fig. 2(b) is a sectional view thereof.

Fig. 3 is an explanatory view schematically showing a semiconductor wafer bonding step in a method for manufacturing a semiconductor device using the semiconductor processing tape according to the embodiment of the present invention.

Fig. 4 is an explanatory view schematically showing a state in which a semiconductor wafer is bonded to a semiconductor processing tape in a method for manufacturing a semiconductor device using the semiconductor processing tape according to the embodiment of the present invention.

Fig. 5 is an explanatory view schematically showing a dicing step in a method for manufacturing a semiconductor device using the semiconductor processing tape according to the embodiment of the present invention.

Fig. 6 is an explanatory view schematically showing an expanding step of a method for manufacturing a semiconductor device using the semiconductor processing tape according to the embodiment of the present invention.

Fig. 7 is an explanatory view schematically showing a pickup step in a method for manufacturing a semiconductor device using the semiconductor processing tape according to the embodiment of the present invention.

Detailed Description

Hereinafter, embodiments of the present invention will be described in detail.

As shown in fig. 1, a semiconductor processing tape 1 according to an embodiment of the present invention includes an adhesive tape 4 including a base film 41, a first adhesive layer 42 provided on the base film 41, and a second adhesive layer 43 provided on the first adhesive layer 42, and an adhesive layer 3 is provided on the second adhesive layer 43.

As shown in fig. 1 and 2, the semiconductor processing tape 1 of the present invention has a base film 41 and a first adhesive layer 42 cut (precut) into a planar shape corresponding to a ring frame R (see fig. 3 to 7). The base film 41 and the first adhesive layer 42 having such a planar shape are also referred to as a first label portion 4a 1. The adhesive layer 3 is cut (precut) to a planar shape corresponding to the planar shape of the semiconductor wafer, and the second adhesive layer 43 is cut (precut) to a planar shape having a smaller size than the adhesive layer 3. The second adhesive layer 43 having such a planar shape is also referred to as a second label portion 4a 2.

The semiconductor processing tape 1 of the present invention is preferably in a form in which a long base tape 2 having a laminate formed by laminating a plurality of adhesive layers 3 having the above-described planar shape, a second label portion 4a2, and a first label portion 4a1 is wound in a roll shape, but in the present embodiment, the tape may be in a form in which the laminate provided on the base tape 2 is cut one by one.

The semiconductor processing tape 1 has a base tape 2, and the base tape 2 is provided with: an adhesive layer 3 having a predetermined planar shape, and an adhesive tape 4 having a second label portion 4a2, a first label portion 4a1, and a peripheral portion 4b surrounding the outer side of the first label portion 4a 1. The peripheral portion 4b is formed of the base film 41 and the first pressure-sensitive adhesive layer 42. Support members 15 are provided along the longitudinal direction at both ends in the short-side direction of the surface of the base tape 2 opposite to the surface provided with the adhesive layer 3.

The first label portion 4a1 has a shape corresponding to the ring frame R for cutting. The ring frame R is ring-shaped. The shape corresponding to the shape of the ring frame R is preferably substantially the same shape as the inside of the ring frame R and is a similar shape having a larger size than the inside of the ring frame R. The shape may not be circular, but is preferably a shape close to a circle, and more preferably a circle. The peripheral portion 4b includes a configuration of completely surrounding the outside of the first label portion 4a1 and a configuration of incompletely surrounding as shown in the figure. The peripheral portion 4b may not be provided, but if provided, the tension applied to the winding of the label portion 4a can be dispersed in a form of being wound in a roll.

The adhesive layer 3 has a predetermined planar shape which is smaller than the label portion 4a so as to be able to be pushed up by the pushing-up member of the pickup apparatus and which is capable of being attached to the ring frame R at the peripheral edge portion of the first label portion 4a1 of the adhesive tape 4. Adhesive layer 3 is preferably substantially the same shape as first label part 4a1 and is preferably a similar shape smaller than the size of first label part 4a 1. The adhesive layer 3 may not be circular, but is preferably nearly circular, and more preferably circular.

The second label portion 4a2 has a shape smaller than the planar shape of the adhesive layer 3. The second label portion 4a2 is preferably substantially the same shape as the adhesive layer 3 and is preferably a similar shape smaller than the size of the adhesive layer 3. The second label portion 4a2 may not be circular, but is preferably approximately circular in shape, and more preferably circular. Further, the shape is preferably larger than the semiconductor wafer W (see fig. 3) bonded to the adhesive layer 3.

The second label portion 4a2 is preferably larger than the semiconductor wafer W to be bonded to the adhesive layer 3. When second label portion 4a2 is smaller than semiconductor wafer W, semiconductor chip C may not be picked up at a portion corresponding to a portion where second label portion 4a2 is not present in the peripheral edge portion of semiconductor wafer W.

Since the planar shape of the adhesive layer 3 is larger than the planar shape of the second adhesive layer 43 (the second label portion 4a2) and the planar shape of the first adhesive layer (the first label portion 4a1) is larger than the planar shape of the adhesive layer 3, the first adhesive layer 42 comes into contact with and adheres to the adhesive layer 3 in the peripheral portion of the second adhesive layer 43.

Each constituent element will be described in detail below.

(substrate film 41)

The base film 41 is not particularly limited, and a known resin such as plastic can be used. In general, a thermoplastic plastic film can be used as the base film 41. The substrate film 41 to be used is preferably a polyolefin such as polyethylene, polypropylene, ethylene-propylene copolymer, and polybutylene, a thermoplastic elastomer such as styrene-hydrogenated isoprene-styrene block copolymer, styrene-isoprene-styrene copolymer, styrene-hydrogenated butadiene-styrene copolymer, and styrene-hydrogenated isoprene/butadiene-styrene copolymer, an ethylene copolymer such as ethylene-vinyl acetate copolymer, ethylene- (meth) acrylic acid ester copolymer, and ethylene- (meth) acrylic acid metal salt ionomer, an engineering plastic such as polyethylene terephthalate, polybutylene terephthalate, polycarbonate, and polymethyl methacrylate, an engineering plastic such as polyethylene, polypropylene, ethylene-propylene copolymer, and polybutylene, an ethylene-styrene copolymer, an ethylene-vinyl acetate copolymer, an ethylene- (meth) acrylic acid copolymer, and a polyethylene-vinyl acetate ionomer, a polyethylene-vinyl acetate copolymer, a polyethylene-vinyl-acrylate copolymer, a polyethylene-vinyl acetate copolymer, a polyethylene-vinyl-acrylate copolymer, a polybutylene-acrylate-based ionomer, or the like, And polymer materials such as soft polyvinyl chloride, semi-hard polyvinyl chloride, polyester, polyurethane, polyamide, polyimide, natural rubber, and synthetic rubber. Further, a mixture of 2 or more selected from these groups or a multilayered product may be used, and may be arbitrarily selected depending on the adhesiveness to the pressure-sensitive adhesive layer 3.

The substrate film 41 may be a commercially available film or may be formed by a general method. The thickness of the base film 41 is not particularly different from that of the base film 41 of a general dicing adhesive tape. Usually 30 to 200 μm, and more preferably 50 to 150 μm.

The surface of the base film 41 that is in contact with the first pressure-sensitive adhesive layer 42 may be subjected to corona treatment or treatment such as primer treatment in order to improve adhesion.

(first adhesive layer 42)

The first pressure-sensitive adhesive layer 42 is preferably a radiation non-curable type that is not cured by irradiation with radiation.

As the resin used for the radiation non-curable first pressure-sensitive adhesive layer 42 that is not cured by irradiation with radiation, a resin containing a constituent unit derived from an alkyl (meth) acrylate monomer and a constituent unit derived from 2-hydroxypropyl acrylate, 2-hydroxyethyl (meth) acrylate, and/or 2-hydroxybutyl acrylate, and a copolymer containing a constituent unit derived from the alkyl (meth) acrylate monomer is crosslinked with an isocyanate compound can be used.

The first pressure-sensitive adhesive layer 42 preferably has an adhesive strength to the SUS304 surface of 1 to 10N/25mm, more preferably 5 to 8N/25mm, under conditions of 23 ℃ and 50% RH, a peel angle of 180 degrees, and a peel speed of 300 mm/min.

When the adhesive strength of the first adhesive layer 42 to the SUS304 surface is less than 1N/25mm, peeling may occur between the first adhesive layer 42 and the adhesive layer 3. When the adhesive force of the first adhesive layer 42 to the SUS304 surface exceeds 10N/25mm, there is a possibility that a paste residue may occur to the ring frame R.

In the present invention, the adhesive force of the first adhesive layer 42 is an adhesive force in a state where the first adhesive layer 42 is provided on the base film 41.

In order to achieve the adhesion to the SUS304 surface within the above range, it is preferable to use an acrylic copolymer comprising 70 to 90 wt% of an alkyl (meth) acrylate monomer having an alkyl group and 4 or more carbon atoms and 10 to 30 wt% of 2-hydroxypropyl acrylate, and having a hydroxyl value of 45 to 100, and polypropylene oxide having a number average molecular weight of 3000 to 10000, and to use an isocyanate-based crosslinking agent for crosslinking.

Examples of the alkyl (meth) acrylate monomer having an alkyl group with 4 or more carbon atoms include butyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, 2-methylpropyl (meth) acrylate, 2-methylbutyl (meth) acrylate, 2-ethylbutyl (meth) acrylate, 2-methylhexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, 1, 2-dimethylbutyl (meth) acrylate, and lauryl (meth) acrylate, and among them, those having an alkyl group with 8 or more carbon atoms are particularly preferable.

In the copolymer forming the binder, the constituent unit derived from the alkyl (meth) acrylate monomer having an alkyl group with 4 or more carbon atoms is preferably contained in an amount of 70 to 90% by mass. When the number of the constituent units derived from the alkyl (meth) acrylate monomer is too large, the crosslinking point of the adhesive is decreased, and sufficient characteristics cannot be obtained, and when the number is too small, the pot life until the adhesive composition is mixed and applied to the base film 41 becomes short, which causes a problem in producing the semiconductor processing tape 1 of the present invention.

Further, 2-hydroxypropyl acrylate is preferably used as the monomer having a crosslinkable functional group, and the monomer has a content of 10 to 30% by mass as a constituent unit. When a functional group-containing monomer such as 2-hydroxyethyl acrylate having a chain length shorter than that of 2-hydroxypropyl acrylate is used, the crosslinking reaction is accelerated, and the pot life is shortened, which causes an obstacle in the production of the semiconductor processing tape 1 of the present invention, and when a monomer having a chain length longer than that of 2-hydroxybutyl acrylate is used, the progress of the crosslinking reaction is slowed, and the completion of the crosslinking reaction is extremely prolonged. When the content of the functional group-containing monomer is less than 10% by mass, the polarity is low, the adhesiveness to the adherend is deteriorated, and peeling of the ring frame R occurs, and when the content exceeds 30% by mass, the adhesiveness to the adherend is excessive, and the adhesive residue generated in the adhesive may remain on the ring frame R.

The hydroxyl value of an acrylic copolymer in which the constituent unit derived from an alkyl (meth) acrylate monomer having an alkyl group with 4 or more carbon atoms is 70 to 90 mass% and the functional group-containing monomer is 2-hydroxyethyl acrylate and/or 2-hydroxypropyl acrylate is preferably 45 to 100 mgKOH/g. When the hydroxyl value is less than 45mgKOH/g, the polarity is low, the adhesion to the adherend is reduced, and the ring frame 9 may peel off, whereas when it exceeds 100mgKOH/g, the adhesion to the adherend is excessive, and the adhesive residue to the ring frame R may occur.

The polypropylene oxide having a number average molecular weight of 3000 to 10000 is not particularly limited as long as it has a number average molecular weight of 3000 to 10000, and can be appropriately selected from known polypropylene oxides. When the number average molecular weight is less than 3000, low molecular weight components are transferred to the adherend surface to increase staining properties, and when it exceeds 10000, compatibility with the acrylic copolymer is deteriorated, and incompatible components are transferred to the adherend surface to increase staining properties, so the number average molecular weight is preferably in the range of 3000 to 10000.

The amount of polypropylene oxide to be blended is not particularly limited, and can be appropriately adjusted within a range in which a desired adhesive strength is obtained, and can be appropriately selected from a range of 0.5 to 5 parts by mass per 100 parts by mass of the acrylic copolymer. When the amount of polypropylene oxide is less than 0.5 parts, the ring frame 9 may be peeled off, and when it exceeds 5 parts, the adhesive may remain on the ring frame R.

The adhesion to the SUS304 surface can be adjusted by appropriately combining the number of carbons of the alkyl group, the blending ratio of the alkyl (meth) acrylate monomer to 2-hydroxypropyl acrylate, the hydroxyl value, the number average molecular weight of polypropylene oxide, the blending ratio of polypropylene oxide, and the like.

The copolymer constituting the adhesive is crosslinked by an isocyanate compound. The isocyanate compound is not particularly limited, and examples thereof include aromatic isocyanates such as 4,4' -diphenylmethane diisocyanate, toluene diisocyanate, xylylene diisocyanate, 4' -diphenyl ether diisocyanate and 4,4' - [2, 2-bis (4-phenoxyphenyl) propane ] diisocyanate, hexamethylene diisocyanate, 2, 4-trimethyl-hexamethylene diisocyanate, isophorone diisocyanate, 4' -dicyclohexylmethane diisocyanate, 2,4' -dicyclohexylmethane diisocyanate, lysine diisocyanate and lysine triisocyanate. Specifically, as a commercially available product, CORONATE L (trade name, manufactured by Polyurethane corporation, japan) or the like can be used.

The content of the isocyanate compound in the first pressure-sensitive adhesive layer 42 is preferably 2 to 12 parts by mass with respect to 100 parts by mass of the copolymer. When the amount of the isocyanate compound is less than 2 parts by mass, crosslinking is insufficient, the coagulability is low, and the amount of the residual paste in the ring frame R increases. When the isocyanate compound is more than 12 parts by mass, the pot life of the adhesive composition mixed and applied to the base film 41 becomes short, and there is a problem in producing the semiconductor processing tape 1 of the present invention.

The pressure-sensitive adhesive composition for forming the first pressure-sensitive adhesive layer 42 may contain, for example, known additives such as a tackifier, an anti-aging agent, a filler, a colorant, a flame retardant, an antistatic agent, a softener, an antioxidant, a plasticizer, and a surfactant, if necessary.

The first pressure-sensitive adhesive layer 42 may have a single-layer form or a laminated form. When the first pressure-sensitive adhesive layer 42 is a plurality of layers, the layer in contact with the pressure-sensitive adhesive layer 3 preferably has an adhesive strength to the SUS304 surface of 1 to 10N/25mm under conditions of 23 ℃ and 50% RH, a peel angle of 180 degrees, and a peel speed of 300 mm/min.

The thickness of the first adhesive layer 42 is preferably 1 to 20 μm, and more preferably 1 to 5 μm. When the first pressure-sensitive adhesive layer 42 is less than 1 μm, the adhesion to the adhesive layer 3 is weak, and in the step of bonding the dicing tape-integrated film for semiconductor back surface to the semiconductor wafer W, when the base material tape 2 covering the adhesive layer 3 is peeled off and tension is applied to the tape for semiconductor processing via the bonding apparatus, the second pressure-sensitive adhesive layer 43 having weak adhesion is locally peeled off from the adhesive layer 3, and the adhesive layer 3 floats, and there is a possibility that the bonding is performed in a state where the adhesive layer 3 is wrinkled when the film is bonded to the semiconductor wafer W. When the first pressure-sensitive adhesive layer 42 is thicker than 15 μm, the adhesiveness may be excessive and the adhesive may remain on the ring frame R.

Although the radiation non-curable pressure-sensitive adhesive that is not cured by irradiation with radiation has been described above, a radiation curable pressure-sensitive adhesive that is cured by irradiation with radiation may be used for the first pressure-sensitive adhesive layer 42.

The configuration of the radiation-curable pressure-sensitive adhesive composition is not particularly limited, but one embodiment includes a composition having, as a base resin, a polymer (a) containing 60 mol% or more of a (meth) acrylate having an alkyl chain with 6 to 12 carbon atoms and having an energy-ray-curable carbon-carbon double bond with an iodine value of 5 to 30 in the pressure-sensitive adhesive composition. Here, the energy ray refers to an ionizing radiation such as an ultraviolet ray or an electron ray.

In the polymer (a), when the amount of introduction of the energy ray-curable carbon-carbon double bond is 5 or more in terms of iodine number, the effect of reducing the adhesive force after irradiation with an energy ray is high, which is excellent. More preferably 10 or more. Further, when the iodine number is 30 or less, the holding force of the chip after the energy ray irradiation until the pickup is high, and the gap between the chips is easily expanded when the chip is expanded immediately before the pickup step, which is excellent. When the gap between the chips can be sufficiently expanded before the pickup step, it is preferable that the image of each chip at the time of pickup be easily recognized and picked up. Further, when the amount of carbon-carbon double bonds introduced is 5 or more and 30 or less in terms of iodine value, the polymer (a) itself is stable and easy to produce, and therefore, it is preferable.

When the glass transition temperature of the polymer (A) is-70 ℃ or higher, the polymer (A) is excellent in heat resistance to heat generated by energy ray irradiation, and more preferably-66 ℃ or higher. Further, when the temperature is 15 ℃ or lower, the effect of preventing scattering of chips after dicing of a wafer having a rough surface state is excellent, and the temperature is more preferably 0 ℃ or lower, and still more preferably-28 ℃ or lower.

The polymer (a) may be produced in any form, but for example, one obtained by mixing an acrylic copolymer with a compound having an energy ray-curable carbon-carbon double bond; an acrylic copolymer having a functional group or a methacrylic copolymer having a functional group (A1), and a compound having a functional group reactive with the functional group and having an energy ray-curable carbon-carbon double bond (A2).

Examples of the functional group-containing methacrylic copolymer (A1) include those obtained by copolymerizing a monomer (A1-1) having a carbon-carbon double bond such as an alkyl acrylate or an alkyl methacrylate and a monomer (A1-2) having a carbon-carbon double bond and a functional group. Examples of the monomer (a1-1) include hexyl acrylate, n-octyl acrylate, isooctyl acrylate, 2-ethylhexyl acrylate, dodecyl acrylate, decyl acrylate, lauryl acrylate having an alkyl chain of 6 to 12 carbon atoms, pentyl acrylate, n-butyl acrylate, isobutyl acrylate, ethyl acrylate, methyl acrylate, and the same methacrylic acid esters as those described above, which are monomers having an alkyl chain of 5 or less carbon atoms.

Since the glass transition temperature is lower when a monomer having a larger carbon number in the alkyl chain is used as the monomer (a1-1), an adhesive composition having a desired glass transition temperature can be produced by appropriately selecting the monomer. In addition, a low molecular weight compound having a carbon-carbon double bond such as vinyl acetate, styrene, or acrylonitrile may be blended for the purpose of improving various properties such as compatibility in addition to the glass transition temperature. In this case, these low-molecular weight compounds are blended in a range of 5 mass% or less of the total mass of the monomer (A1-1).

On the other hand, examples of the functional group of the monomer (A1-2) include a carboxyl group, a hydroxyl group, an amino group, a cyclic acid anhydride group, an epoxy group, an isocyanate group and the like, and examples of the monomer (A1-2) include acrylic acid, methacrylic acid, cinnamic acid, itaconic acid, fumaric acid, phthalic acid (phthalic acid), 2-hydroxyalkyl acrylates, 2-hydroxyalkyl methacrylates, glycol monoacrylates, glycol monomethacrylates, N-methylolacrylamide, N-methylolmethacrylamide, allyl alcohol, N-alkylaminoethyl acrylates, N-alkylaminoethyl methacrylates, acrylamides, methacrylamides, maleic anhydride, itaconic anhydride, fumaric anhydride, phthalic anhydride (phthalic anhydride) and phthalic anhydride (phthalic anhydride), Glycidyl acrylate, glycidyl methacrylate, allyl glycidyl ether, and the like.

In addition, in the compound (a2), examples of the functional group to be used include a hydroxyl group, an epoxy group, an isocyanate group, and the like when the functional group of the compound (a1) is a carboxyl group or a cyclic acid anhydride group, an epoxy group, an isocyanate group, and the like when the functional group is a hydroxyl group, an epoxy group, an isocyanate group, and the like when the functional group is an amino group, and a carboxyl group, a cyclic acid anhydride group, an amino group, and the like when the functional group is an epoxy group, and the same groups as those exemplified as the specific examples of the monomer (a1-2) are exemplified as specific examples. Further, as the compound (a2), one obtained by urethanizing a part of the isocyanate groups of the polyisocyanate compound with a monomer having a hydroxyl group or a carboxyl group and an energy ray-curable carbon-carbon double bond can also be used.

In the reaction of compound (a1) and compound (a2), unreacted functional groups remain, whereby a desired product can be produced in terms of characteristics such as acid value and hydroxyl value. When the OH groups remain so that the hydroxyl value of the polymer (a) is 5 to 100, the adhesive force after irradiation with energy rays is reduced, whereby the adhesive residue to the ring frame R can be further reduced. When the hydroxyl value of the polymer (a) is 5 or more, it is excellent in the effect of reducing the adhesive force after energy ray irradiation, and when it is 100 or less, it is excellent in the fluidity of the adhesive after energy ray irradiation. When the acid value is 30 or less, the fluidity of the binder is excellent.

In the synthesis of the polymer (a), as the organic solvent in the case of carrying out the reaction by solution polymerization, ketone, ester, alcohol, and aromatic solvents can be used, but among them, toluene, ethyl acetate, isopropyl alcohol, benzyl cellosolve, ethyl cellosolve, acetone, methyl ethyl ketone, and other solvents which are generally good solvents for acrylic polymers and have a boiling point of 60 to 120 ℃ are preferable, and as the polymerization initiator, azo-based, such as α, α' -azobisisobutyronitrile, and radical generators, such as benzoyl peroxide, and other organic peroxides, are usually used. In this case, if necessary, a catalyst and a polymerization inhibitor may be used in combination, and the polymerization temperature and the polymerization time may be adjusted to obtain the polymer (A) having a desired molecular weight. In addition, for the adjustment of the molecular weight, it is preferable to use a thiol or carbon tetrachloride solvent. The reaction is not limited to solution polymerization, and may be other methods such as bulk polymerization and suspension polymerization.

In the semiconductor processing tape 1 of the present invention, the resin composition constituting the first pressure-sensitive adhesive layer 42 may further contain a compound (B) that functions as a crosslinking agent in addition to the polymer (a). For example, polyisocyanates, melamine/formaldehyde resins, and epoxy resins can be used, and these may be used alone or in combination of 2 or more. The compound (B) reacts with the polymer (a) or the base film 41, and the resultant crosslinked structure can improve the cohesive force of the adhesive containing the polymers (a) and (B) as main components after the adhesive composition is applied.

The polyisocyanate is not particularly limited, and examples thereof include aromatic isocyanates such as 4,4' -diphenylmethane diisocyanate, tolylene diisocyanate, xylylene diisocyanate, 4' -diphenyl ether diisocyanate and 4,4' - [2, 2-bis (4-phenoxyphenyl) propane ] diisocyanate, hexamethylene diisocyanate, 2, 4-trimethyl-hexamethylene diisocyanate, isophorone diisocyanate, 4' -dicyclohexylmethane diisocyanate, 2,4' -dicyclohexylmethane diisocyanate, lysine diisocyanate and lysine triisocyanate, and specifically CORONATE L (trade name, manufactured by polycarbamane, japan) can be used. Specific examples of the melamine/formaldehyde resin include NIKALAC MX-45 (trade name, manufactured by Sanko chemical industries, Ltd.), MELAN (Japanese: メラン) (trade name, manufactured by Hitachi chemical industries, Ltd.). As the epoxy resin, TETRAD-X (trade name, manufactured by Mitsubishi chemical Co., Ltd.) or the like can be used. In the present invention, in particular, polyisocyanates are preferably used.

The adhesive layer in which the amount of the compound (B) added is 0.1 part by mass or more per 100 parts by mass of the polymer (a) is excellent in cohesive force. More preferably 0.5 parts by mass or more. The adhesive layer of 10 parts by mass or less is excellent in suppressing rapid gelation during coating, and the workability such as mixing and coating of the adhesive is favorable. More preferably 5 parts by mass or less.

In the present invention, the first pressure-sensitive adhesive layer 42 may contain a photopolymerization initiator (C). The photopolymerization initiator (C) contained in the first pressure-sensitive adhesive layer 42 is not particularly limited, and conventionally known ones can be used. Examples thereof include benzophenones such as benzophenone, 4' -dimethylaminobenzophenone, 4' -diethylaminobenzophenone and 4,4' -dichlorobenzophenone, acetophenones such as acetophenone and diethoxyacetophenone, anthraquinones such as 2-ethylanthraquinone and tert-butylanthraquinone, 2-chlorothioxanthone, benzoin ethyl ether, benzoin isopropyl ether, benzil, 2,4, 5-triarylimidazole dimer (profen dimer), acridine compounds, and these compounds may be used alone or in combination of 2 or more. The amount of the photopolymerization initiator (C) added is preferably 0.1 part by mass or more, more preferably 0.5 part by mass or more, per 100 parts by mass of the polymer (a). The upper limit is preferably 10 parts by mass or less, and more preferably 5 parts by mass or less.

In addition, a tackifier, an adhesion regulator, a surfactant, and the like, or other modifiers, and the like may be blended as necessary in the energy ray-curable adhesive used in the present invention. Further, an inorganic compound filler may be appropriately added.

When a radiation-curable pressure-sensitive adhesive that is cured by irradiation with radiation is used as the first pressure-sensitive adhesive layer 42, the adhesive strength to the SUS304 surface is preferably 1 to 10N/25mm under conditions of a peeling angle of 180 degrees and a peeling speed of 300mm/min at 23 ℃ and 50% RH before irradiation with radiation.

(second adhesive layer 43)

The second pressure-sensitive adhesive layer 43 is preferably a radiation non-curable type that is not cured by irradiation with radiation.

As the resin used for the radiation non-curable second pressure-sensitive adhesive layer 43 that is not cured by irradiation with radiation, a resin containing a constituent unit derived from an alkyl (meth) acrylate monomer and a constituent unit derived from 2-hydroxypropyl acrylate, 2-hydroxyethyl (meth) acrylate, and/or 2-hydroxybutyl acrylate, and a copolymer containing a constituent unit derived from the alkyl (meth) acrylate monomer is crosslinked with an isocyanate compound can be used.

The second pressure-sensitive adhesive layer 43 preferably has an adhesive strength to the SUS304 surface of 0.1 to 0.6N/25mm, more preferably 0.1 to 0.4N/25mm, under conditions of 23 ℃ and 50% RH, a peel angle of 180 degrees, and a peel speed of 300 mm/min.

When the adhesive strength of the second adhesive layer 43 to the SUS304 surface is less than 0.1N/25mm, the chips C may be peeled off from the second adhesive layer 43 during dicing and may be scattered when the semiconductor wafer W is diced into small-sized chips C. If the adhesive force of the second adhesive layer 43 to the SUS304 surface exceeds 0.6N/25mm, the chip C with the adhesive layer 3 may not be picked up when the semiconductor wafer W is diced into large-sized chips C.

In the present application, the adhesion of the second adhesive layer 43 is: the adhesive strength in the state of the adhesive tape, that is, in the state of the adhesive tape 1 without the adhesive layer 3. In the present embodiment, the adhesive strength is obtained when the base film 41, the first pressure-sensitive adhesive layer 42, and the second pressure-sensitive adhesive layer 43 are laminated in this order.

In order to achieve the adhesion to the SUS304 surface within the above range, it is preferable to use an acrylic copolymer comprising 70 to 90 mass% of an alkyl (meth) acrylate monomer having an alkyl group and 4 or more carbon atoms and 10 to 30 mass% of 2-hydroxypropyl acrylate, and having a hydroxyl value of 45 to 100, and polypropylene oxide having a number average molecular weight of 3000 to 10000, and to use an isocyanate-based crosslinking agent for crosslinking.

Further, 2-hydroxypropyl acrylate is preferably used as the monomer having a crosslinkable functional group, and the monomer has a content of 10 to 30% by mass as a constituent unit. When a functional group-containing monomer such as 2-hydroxyethyl acrylate having a chain length shorter than that of 2-hydroxypropyl acrylate is used, the crosslinking reaction is accelerated, and the pot life is shortened, which causes an obstacle in the production of the semiconductor processing tape 1 of the present invention, and when a monomer having a chain length longer than that of 2-hydroxybutyl acrylate is used, the progress of the crosslinking reaction is slowed, and the completion of the crosslinking reaction is extremely prolonged. When the content of the functional group-containing monomer is less than 10% by mass, the polarity is low, the adhesion to the adherend is lowered, and the chips are scattered, and when the content exceeds 30% by mass, the adhesion to the adherend is excessive, and the pickup failure may occur.

The hydroxyl value of an acrylic copolymer in which the constituent unit derived from an alkyl (meth) acrylate monomer having an alkyl group with 4 or more carbon atoms is 70 to 90 mass% and the functional group-containing monomer is 2-hydroxyethyl acrylate and/or 2-hydroxypropyl acrylate is preferably 45 to 100 mgKOH/g. When the hydroxyl value is less than 45mgKOH/g, the polarity is low, the adhesion to the adherend is reduced, and chip scattering occurs, and when it exceeds 100mgKOH/g, the adhesion to the adherend is excessive, and pickup failure may occur.

The polypropylene oxide having a number average molecular weight of 3000 to 10000 is not particularly limited as long as it has a number average molecular weight of 3000 to 10000, and can be appropriately selected from known polypropylene oxides. When the number average molecular weight is less than 3000, low molecular weight components are transferred to the adherend surface, increasing fouling, and when it exceeds 10000, compatibility with the acrylic copolymer is deteriorated, incompatible components are transferred to the adherend surface, increasing fouling, and therefore, the number average molecular weight is preferably in the range of 3000 to 10000.

The amount of polypropylene oxide to be blended is not particularly limited, and can be appropriately adjusted within a range in which a desired adhesive strength is obtained, and can be appropriately selected from a range of 0.5 to 5 parts by mass per 100 parts by mass of the acrylic copolymer. When the amount of polypropylene oxide blended is less than 0.5 parts, the chips may be scattered, and when it exceeds 5 parts, poor pickup may occur.

The content of the isocyanate compound in the second pressure-sensitive adhesive layer 43 is preferably 2 to 12 parts by mass with respect to 100 parts by mass of the copolymer. When the amount of the isocyanate compound is less than 2 parts by mass, crosslinking is insufficient, the coagulability is low, and the pickup failure increases. When the isocyanate compound is more than 12 parts by mass, the pot life of the adhesive composition for film formation becomes short, and there is a problem in producing the semiconductor processing tape 1 of the present invention.

The pressure-sensitive adhesive composition for forming the second pressure-sensitive adhesive layer 43 may contain, for example, known additives such as a tackifier, an anti-aging agent, a filler, a colorant, a flame retardant, an antistatic agent, a softener, an antioxidant, a plasticizer, and a surfactant, if necessary.

The second pressure-sensitive adhesive layer 43 may have a single-layer form or a laminated form. When the second pressure-sensitive adhesive layer 432 is a plurality of layers, the layer in contact with the pressure-sensitive adhesive layer 3 preferably has an adhesive strength to the SUS304 surface of 0.1 to 0.6N/25mm under conditions of 23 ℃ and 50% RH, a peel angle of 180 degrees, and a peel speed of 300 mm/min.

The thickness of the second pressure-sensitive adhesive layer 43 is preferably set to be 5 to 30 μm in total thickness with the first pressure-sensitive adhesive layer 42, and more preferably set to be 10 to 15 μm in total thickness with the first pressure-sensitive adhesive layer 42, from the viewpoint of pickup properties.

Although the radiation non-curable pressure-sensitive adhesive that is not cured by irradiation with radiation has been described above, a radiation curable pressure-sensitive adhesive that is cured by irradiation with radiation may be used for the second pressure-sensitive adhesive layer 43.

In the polymer (a), when the amount of introduction of the energy ray-curable carbon-carbon double bond is 5 or more in terms of iodine number, the effect of reducing the adhesive force after irradiation with an energy ray is high, which is excellent. More preferably 10 or more. Further, when the iodine number is 30 or less, the holding force of the chip after the energy ray irradiation until the pickup is high, and the gap between the chips is easily expanded when the chip is expanded immediately before the pickup step. When the gap between the chips can be sufficiently expanded before the pickup step, it is preferable that the image recognition of each chip at the time of pickup is facilitated, and the pickup is facilitated. Further, the amount of carbon-carbon double bonds introduced is preferably 5 to 30 in terms of iodine value, since the polymer (a) itself is stable and can be easily produced.

The component having an alkyl chain of 6 or more in the monomer (a1-1) is excellent in the pickup property because it can reduce the peeling force between the second pressure-sensitive adhesive layer 43 and the adhesive layer 3. Further, the components of 12 or less have a low elastic modulus at room temperature, and are excellent in adhesion at the interface between the second pressure-sensitive adhesive layer 43 and the adhesive layer 3.

Further, as the monomer (a1-1), the larger the carbon number of the alkyl chain, the lower the glass transition temperature, and therefore, by appropriate selection, an adhesive composition having a desired glass transition temperature can be prepared. In addition, a low molecular weight compound having a carbon-carbon double bond such as vinyl acetate, styrene, or acrylonitrile may be blended for the purpose of improving various properties such as compatibility in addition to the glass transition temperature. In this case, these low-molecular weight compounds are blended in a range of 5 mass% or less of the total mass of the monomer (A1-1).

In the reaction of compound (a1) and compound (a2), unreacted functional groups remain, whereby a desired product can be produced in terms of characteristics such as acid value and hydroxyl value. When the OH group remains so that the hydroxyl value of the polymer (a) is 5 to 100, the risk of a pickup error can be further reduced by reducing the adhesive force after irradiation with an energy ray. When the hydroxyl value of the polymer (a) is 5 or more, it is excellent in the effect of reducing the adhesive force after energy ray irradiation, and when it is 100 or less, it is excellent in the fluidity of the adhesive after energy ray irradiation. When the acid value is 30 or less, the fluidity of the binder is excellent.

In the semiconductor processing tape 1 of the present invention, the resin composition constituting the second pressure-sensitive adhesive layer 43 may further contain a compound (B) that functions as a crosslinking agent in addition to the polymer (a). For example, polyisocyanates, melamine/formaldehyde resins, and epoxy resins can be used, and these may be used alone or in combination of 2 or more. The compound (B) reacts with the polymer (a) or the adhesive layer 3, and as a result, a cross-linked structure is formed, and after the adhesive composition is applied, the cohesive force of the adhesive containing the polymers (a) and (B) as main components can be improved.

The polyisocyanate is not particularly limited, and examples thereof include aromatic isocyanates such as 4,4' -diphenylmethane diisocyanate, tolylene diisocyanate, xylylene diisocyanate, 4' -diphenyl ether diisocyanate and 4,4' - [2, 2-bis (4-phenoxyphenyl) propane ] diisocyanate, hexamethylene diisocyanate, 2, 4-trimethyl-hexamethylene diisocyanate, isophorone diisocyanate, 4' -dicyclohexylmethane diisocyanate, 2,4' -dicyclohexylmethane diisocyanate, lysine diisocyanate and lysine triisocyanate, and specifically CORONATE L (trade name, manufactured by Polyurethane corporation, japan) can be used. Specific examples of the melamine/formaldehyde resin include NIKALAC MX-45 (trade name, manufactured by Sanko chemical industries, Ltd.), MELAN (trade name, manufactured by Hitachi chemical industries, Ltd.), and the like. As the epoxy resin, TETRAD-X (trade name, manufactured by Mitsubishi chemical Co., Ltd.) or the like can be used. In the present invention, in particular, polyisocyanates are preferably used.

The adhesive layer in which the amount of the compound (B) added is 0.1 part by mass or more per 100 parts by mass of the polymer (a) is excellent in cohesive force. More preferably 0.5 parts by mass or more. The adhesive layer of 10 parts by mass or less is excellent in suppressing rapid gelation during coating, and the workability such as mixing and coating of the adhesive is good. More preferably 5 parts by mass or less.

In the present invention, the second pressure-sensitive adhesive layer 43 may contain a photopolymerization initiator (C). The photopolymerization initiator (C) contained in the second pressure-sensitive adhesive layer 43 is not particularly limited, and conventionally known ones can be used. Examples thereof include benzophenones such as benzophenone, 4' -dimethylaminobenzophenone, 4' -diethylaminobenzophenone and 4,4' -dichlorobenzophenone, acetophenones such as acetophenone and diethoxyacetophenone, anthraquinones such as 2-ethylanthraquinone and tert-butylanthraquinone, 2-chlorothioxanthone, benzoin ethyl ether, benzoin isopropyl ether, benzil, 2,4, 5-triarylimidazole dimer (profen dimer), acridine compounds, and these compounds may be used alone or in combination of 2 or more. The amount of the photopolymerization initiator (C) added is preferably 0.1 part by mass or more, more preferably 0.5 part by mass or more, per 100 parts by mass of the polymer (a). The upper limit is preferably 10 parts by mass or less, and more preferably 5 parts by mass or less.

When a radiation-curable pressure-sensitive adhesive that is cured by irradiation with radiation is used as the second pressure-sensitive adhesive layer 43, the adhesive strength to the SUS304 surface is preferably 0.1 to 0.6N/25mm under conditions of a peeling angle of 180 degrees and a peeling speed of 300mm/min at 23 ℃ and 50% RH before irradiation with radiation.

(adhesive layer 3)

In the semiconductor processing tape 1 of the present invention, the adhesive layer 3 is peeled from the adhesive layer 43 and adhered to the chip C when the chip C is picked up after the semiconductor wafer W is bonded and diced. Then, the adhesive is used for fixing the chip C to a substrate or a lead frame.

The adhesive layer 3 is not particularly limited, and a film-like adhesive generally used for semiconductor wafers may be used, and examples thereof include those containing a thermoplastic resin and a thermopolymerizing component. The thermoplastic resin used in the adhesive layer 3 of the present invention is preferably a thermoplastic resin or a resin that has thermoplasticity in an uncured state and forms a crosslinked structure after heating, and is not particularly limited, but one embodiment thereof includes a thermoplastic resin having a weight average molecular weight of 5000 to 200,000 and a glass transition temperature of 0 to 150 ℃. In another embodiment, the thermoplastic resin has a weight average molecular weight of 100,000 to 1,000,000 and a glass transition temperature of-50 to 20 ℃.

Examples of the former thermoplastic resin include polyimide resins, polyamide resins, polyetherimide resins, polyamideimide resins, polyester resins, polyesterimide resins, phenoxy resins, polysulfone resins, polyethersulfone resins, polyphenylene sulfide resins, and polyetherketone resins, among which polyimide resins and phenoxy resins are preferably used, and polymers containing functional groups are preferably used as the latter thermoplastic resins.

The polyimide resin can be obtained by condensation reaction of tetracarboxylic dianhydride (Japanese patent publication No. テトラカルボン) with diamine by a known method. That is, an addition reaction is carried out in an organic solvent at a reaction temperature of 80 ℃ or less, preferably 0 to 60 ℃, using equimolar or nearly equimolar amounts of tetracarboxylic dianhydride and diamine (the order of addition of the components is arbitrary). As the reaction proceeds, the viscosity of the reaction solution gradually increases, and polyamic acid as a precursor of polyimide is produced. The polyamic acid can be depolymerized by heating at 50 to 80 ℃ to adjust its molecular weight. The polyimide resin can be obtained by dehydration ring closure of the above reactant (polyamic acid). The dehydration ring closure can be carried out by a thermal ring closure method using heat treatment and a chemical ring closure method using a dehydrating agent.

The tetracarboxylic dianhydride used as a raw material for the polyimide resin is not particularly limited, and examples thereof include 1,2- (ethylene) bis (trimellitic anhydride), 1,3- (trimethylene) bis (trimellitic anhydride), 1,4- (tetramethylene) bis (trimellitic anhydride), 1,5- (pentamethylene) bis (trimellitic anhydride), 1,6- (hexamethylene) bis (trimellitic anhydride), 1,7- (heptamethylene) bis (trimellitic anhydride), 1,8- (octamethylene) bis (trimellitic anhydride), 1,9- (nonamethylene) bis (trimellitic anhydride), 1,10- (decamethylene) bis (trimellitic anhydride), 1,12- (dodecamethylene) bis (trimellitic anhydride), 1,16- (hexadecamethylene) bis (trimellitic anhydride), 1,18- (octadecylidene) bis (trimellitic anhydride), pyromellitic dianhydride, 3,3',4,4' -biphenyltetracarboxylic dianhydride, 2',3,3' -biphenyltetracarboxylic dianhydride, 2-bis (3, 4-dicarboxyphenyl) propane dianhydride, 2-bis (2, 3-dicarboxyphenyl) propane dianhydride, 1-bis (2, 3-dicarboxyphenyl) ethane dianhydride, 1-bis (3, 4-dicarboxyphenyl) ethane dianhydride, bis (2, 3-dicarboxyphenyl) methane dianhydride, bis (3, 4-dicarboxyphenyl) sulfonic dianhydride, 3,4,9, 10-perylenetetracarboxylic dianhydride, Bis (3, 4-dicarboxyphenyl) ether dianhydride, benzene-1, 2,3, 4-tetracarboxylic dianhydride, 3,4,3',4' -benzophenonetetracarboxylic dianhydride, 2,3,2',3' -benzophenonetetracarboxylic dianhydride, 3,3',4' -benzophenonetetracarboxylic dianhydride, 1,2,5, 6-naphthalenetetracarboxylic dianhydride, 1,4,5, 8-naphthalenetetracarboxylic dianhydride, 2,3,6, 7-naphthalenetetracarboxylic dianhydride, 1,2,4, 5-naphthalenetetracarboxylic dianhydride, 2, 6-dichloronaphthalene-1, 4,5, 8-tetracarboxylic dianhydride, 2, 7-dichloronaphthalene-1, 4,5, 8-tetracarboxylic dianhydride, 2,3,6, 7-tetrachloronaphthalene-1, 4,5, 8-tetracarboxylic dianhydride, Phenanthrene-1, 8,9, 10-tetracarboxylic dianhydride, pyrazine-2, 3,5, 6-tetracarboxylic dianhydride, thiophene-2, 3,5, 6-tetracarboxylic dianhydride, 2,3,3',4' -biphenyltetracarboxylic dianhydride, 3,4,3',4' -biphenyltetracarboxylic dianhydride, 2,3,2',3' -biphenyltetracarboxylic dianhydride, bis (3, 4-dicarboxyphenyl) dimethylsilane dianhydride, bis (3, 4-dicarboxyphenyl) methylphenylsilane dianhydride, bis (3, 4-dicarboxyphenyl) biphenylsilane dianhydride, 1, 4-bis (3, 4-dicarboxyphenyldimethylsilyl) benzene dianhydride, 1, 3-bis (3, 4-dicarboxyphenyl) -1,1,3, 3-tetramethylbicyclohexane dianhydride, P-phenylene bis (trimellitic anhydride), ethylene tetracarboxylic dianhydride, 1,2,3, 4-butane tetracarboxylic dianhydride, decahydronaphthalene-1, 4,5, 8-tetracarboxylic dianhydride, 4, 8-dimethyl-1, 2,3,5,6, 7-hexahydronaphthalene-1, 2,5, 6-tetracarboxylic dianhydride, cyclopentane-1, 2,3, 4-tetracarboxylic dianhydride, pyrrolidine-2, 3,4, 5-tetracarboxylic dianhydride, 1,2,3, 4-cyclobutane tetracarboxylic dianhydride, bis (exo-bicyclo [2,2,1] heptane-2, 3-dicarboxylic dianhydride, bicyclo- [2,2,2] -oct-7-ene-2, 3,5, 6-tetracarboxylic dianhydride, 2, 2-bis (3, 4-dicarboxyphenyl) hexafluoropropane dianhydride, 2-bis [4- (3, 4-dicarboxyphenyl) phenyl ] hexafluoropropane dianhydride, 4' -bis (3, 4-dicarboxyphenoxy) diphenyl sulfide dianhydride, 1, 4-bis (2-hydroxyhexafluoroisopropyl) benzenebis (trimellitic anhydride), 1, 3-bis (2-hydroxyhexafluoroisopropyl) benzenebis (trimellitic anhydride), 5- (2, 5-dioxotetrahydrofuryl) -3-methyl-3-cyclohexene-1, 2-dicarboxylic dianhydride, tetrahydrofuran-2, 3,4, 5-tetracarboxylic dianhydride, and the like, and 1 or 2 or more of these may be used in combination.

The diamine used as a raw material of the polyimide is not particularly limited, and examples thereof include o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, 3 '-diaminodiphenyl ether, 3,4' -diaminodiphenyl ether, 4 '-diaminodiphenyl ether, 3' -diaminodiphenylmethane, 3,4 '-diaminodiphenylmethane, 4' -diaminodiphenyl ether methane, bis (4-amino-3, 5-dimethylphenyl) methane, bis (4-amino-3, 5-diisopropylphenyl) methane, 3 '-diaminodiphenyldifluoromethane, 3,4' -diaminodiphenyldifluoromethane, 4 '-diaminodiphenyldifluoromethane, 3' -diaminodiphenylsulfone, and the like, 3,4' -diaminodiphenyl sulfone, 4' -diaminodiphenyl sulfone, 3' -diaminodiphenyl sulfide, 3,4' -diaminodiphenyl sulfide, 4' -diaminodiphenyl sulfide, 3' -diaminodiphenyl ketone, 3,4' -diaminodiphenyl ketone, 4' -diaminodiphenyl ketone, 2-bis (3-aminophenyl) propane, 2' - (3,4' -diaminodiphenyl) propane, 2-bis (4-aminophenyl) propane, 2-bis (3-aminophenyl) hexafluoropropane, 2- (3,4' -diaminodiphenyl) hexafluoropropane, 2-bis (4-aminophenyl) hexafluoropropane, 1, 3-bis (3-aminophenoxy) benzene, 1, 4-bis (4-aminophenoxy) benzene, 3' - (1, 4-phenylenebis (1-methylethylidene)) dianiline, 3,4' - (1, 4-phenylenebis (1-methylethylidene)) dianiline, 4' - (1, 4-phenylenebis (1-methylethylidene)) dianiline, 2-bis (4- (3-aminophenoxy) phenyl) propane, 2-bis (4- (4-aminophenoxy) phenyl) propane, 2-bis (4- (3-aminophenoxy) phenyl) hexafluoropropane, 2-bis (4- (4-aminophenoxy) phenyl) hexafluoropropane, Bis (4- (3-aminophenoxy) phenyl) sulfide, bis (4- (4-aminophenoxy) phenyl) sulfide, bis (4- (3-aminophenoxy) phenyl) sulfone, bis (4- (4-aminophenoxy) phenyl) sulfone, an aromatic diamine such as 3, 5-diaminobenzoic acid, 1, 2-diaminoethane, 1, 3-diaminopropane, 1, 4-diaminobutane, 1, 5-diaminopentane, 1, 6-diaminohexane, 1, 7-diaminoheptane, 1, 8-diaminooctane, 1, 9-diaminononane, 1, 10-diaminodecane, 1, 11-diaminoundecane, 1, 12-diaminododecane, 1, 2-diaminocyclohexane, a diaminopolysiloxane represented by the following general formula (1), a salt thereof, a water-soluble organic solvent, and the like, Aliphatic diamines such as polyoxyalkylene diamines including 1, 3-bis (aminomethyl) cyclohexane and JEFFAMINE D-230, D-400, D-2000, D-4000, ED-600, ED-900, ED-2001 and EDR-148 manufactured by SANTECHNOCHEMICAL Co. 1 or 2 or more of these may be used in combination. The glass transition temperature of the polyimide resin is preferably 0 to 200 ℃ and the weight average molecular weight is preferably 1 to 20 ten thousand.

[ solution 1]

(in the formula, R₁And R₂Each represents a divalent hydrocarbon group having 1 to 30 carbon atoms, which may be the same or different, R₃And R₄Each represents a monovalent hydrocarbon group, which may be the same or different, and m is an integer of 1 or more. )

As the phenoxy resin which is one of the above-mentioned preferable thermoplastic resins, a resin obtained by a method of reacting various bisphenols with epichlorohydrin or a method of reacting a liquid epoxy resin with bisphenol is preferable, and as the bisphenol, bisphenol a, bisphenol AF, bisphenol AD, bisphenol F, bisphenol S are exemplified. The phenoxy resin has a structure similar to that of an epoxy resin, and therefore, is excellent in compatibility with the epoxy resin and suitable for imparting good adhesion to an adhesive film.

Examples of the phenoxy resin used in the present invention include resins having a repeating unit represented by the following general formula (2).

[ solution 2]

In the general formula (2), X represents a single bond or a 2-valent linking group. As the linking group having a valence of 2, there may be mentioned alkylene, phenylene, -O-, -S-, -SO-or-SO₂-. Here, the alkylene group is preferably an alkylene group having 1 to 10 carbon atoms, and more preferably-C (R)₁)(R₂)-。R₁、R₂The alkyl group is preferably a linear or branched alkyl group having 1 to 8 carbon atoms, and examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an isooctyl group, a 2-ethylhexyl group, and a1, 3, 3-trimethylbutyl group. The alkyl group may be substituted with a halogen atom, and examples thereof include a trifluoromethyl group. X is preferably alkylene, -O-, -S-, fluorenyl or-SO₂-, more preferably alkylene, -SO₂-. Among them, preferred is-C (CH)₃)₂-、-CH(CH₃)-、-CH₂-、-SO₂-, more preferably-C (CH)₃)₂-、-CH(CH₃)-、-CH₂-C (CH) is particularly preferred₃)₂-。

The phenoxy resin represented by the above general formula (2) may be a resin having a plurality of repeating units different from X of the above general formula (2) as long as it has a repeating unit, or may be composed of only repeating units having the same X. In the present invention, a resin composed of only the same repeating unit as X is preferred.

When the phenoxy resin represented by the above general formula (2) contains a polar substituent such as a hydroxyl group or a carboxyl group, the compatibility with the thermally polymerizable component is improved, and uniform appearance and properties can be provided.

When the mass average molecular weight of the phenoxy resin is 5000 or more, the phenoxy resin is excellent in film-forming properties. More preferably 10,000 or more, and still more preferably 30,000 or more. When the mass average molecular weight is 150,000 or less, the resin composition is preferably used in view of fluidity during thermocompression bonding and compatibility with other resins. More preferably 100,000 or less. When the glass transition temperature is-50 ℃ or higher, the film-forming property is excellent, and the glass transition temperature is more preferably 0 ℃ or higher, and still more preferably 50 ℃ or higher. When the glass transition temperature is 150 ℃, the adhesive force of adhesive layer 13 at the time of die bonding is excellent, and more preferably 120 ℃ or lower, and still more preferably 110 ℃ or lower.

On the other hand, examples of the functional group of the polymer having the functional group include a glycidyl group, an acryloyl group, a methacryloyl group, a hydroxyl group, a carboxyl group, an isocyanurate group, an amino group, and an amide group, and among them, a glycidyl group is preferable.

Examples of the high molecular weight component having a functional group include (meth) acrylic copolymers having a functional group such as a glycidyl group, a hydroxyl group, and a carboxyl group.

As the (meth) acrylic copolymer, for example, a (meth) acrylate copolymer, an acrylic rubber, and the like can be used, and an acrylic rubber is preferable. The acrylic rubber is a rubber mainly composed of an acrylic ester and mainly composed of a copolymer of butyl acrylate and acrylonitrile or a copolymer of ethyl acrylate and acrylonitrile.

When the functional group contains a glycidyl group, the amount of the glycidyl group-containing repeating unit is preferably 0.5 to 6.0% by weight, more preferably 0.5 to 5.0% by weight, and particularly preferably 0.8 to 5.0% by weight. The glycidyl group-containing repeating unit is a constituent monomer of a glycidyl group-containing (meth) acrylic copolymer, and specifically is glycidyl acrylate or glycidyl methacrylate. When the amount of the glycidyl group-containing repeating unit is within this range, the adhesive strength can be secured and gelation can be prevented.

Examples of the constituent monomer of the (meth) acrylic copolymer other than glycidyl acrylate and glycidyl methacrylate include ethyl (meth) acrylate and butyl (meth) acrylate, and these monomers may be used alone or in combination of 2 or more. In the present invention, ethyl (meth) acrylate means ethyl acrylate and/or ethyl methacrylate. The mixing ratio when the combination functional monomers are used may be determined in consideration of the glass transition temperature of the (meth) acrylic copolymer. When the glass transition temperature is-50 ℃ or higher, it is preferable that the film has excellent film-forming properties and can suppress excessive stickiness at ordinary temperature conditions. When the tackiness under normal temperature conditions is excessive, handling of the adhesive layer becomes difficult. More preferably-20 ℃ or higher, and still more preferably 0 ℃ or higher. When the glass transition temperature is 30 ℃ or lower, the adhesive strength of the adhesive layer at the time of die bonding is excellent, and more preferably 20 ℃ or lower.

When the monomer is polymerized to produce a high molecular weight component containing a functional monomer, the polymerization method is not particularly limited, and for example, a method such as bead polymerization or solution polymerization can be used, and bead polymerization is preferable.

In the present invention, when the weight average molecular weight of the high molecular weight component containing the functional monomer is 100,000 or more, the high molecular weight component is excellent in film forming property, more preferably 200,000 or more, and further preferably 500,000 or more. When the weight average molecular weight is adjusted to 2,000,000 or less, the adhesive layer 3 is excellent in improvement of heat fluidity at the time of die bonding. When the heat fluidity of the adhesive layer 3 is improved during die bonding, the adhesive layer 3 can be satisfactorily adhered to the adherend to improve the adhesive strength, and the irregularities of the adherend can be embedded to easily suppress voids. More preferably 1,000,000 or less, and still more preferably 800,000 or less, and when it is 500,000 or less, a further significant effect can be obtained.

The thermal polymerization component is not particularly limited as long as it is polymerized by heat, and examples thereof include compounds having a functional group such as a glycidyl group, an acryloyl group, a methacryloyl group, a hydroxyl group, a carboxyl group, an isocyanurate group, an amino group, an amide group, and the like, and a trigger material, and these compounds may be used alone or in combination of 2 or more, but when the heat resistance of the adhesive layer 3 is considered, it is preferable to contain a thermosetting resin which is cured by heat and gives an adhesive action together with a curing agent and an accelerator. Examples of the thermosetting resin include epoxy resin, acrylic resin, silicone resin, phenol resin, thermosetting polyimide resin, polyurethane resin, melamine resin, and urea resin, and particularly, epoxy resin is most preferably used in order to obtain an adhesive layer having excellent heat resistance, workability, and reliability.

The epoxy resin is not particularly limited as long as it has an adhesive action by curing, and a bifunctional epoxy resin such as bisphenol a epoxy resin, a phenol novolac epoxy resin, a cresol novolac epoxy resin, or the like can be used. In addition, generally known resins such as polyfunctional epoxy resins, glycidyl amine type epoxy resins, heterocyclic ring-containing epoxy resins, and alicyclic epoxy resins can be used.

Examples of the bisphenol A type epoxy resin include Epicoat series (Epicoat807, Epicoat815, Epicoat825, Epicoat827, Epicoat828, Epicoat834, Epicoat1001, Epicoat1004, Epicoat1007, and Epicoat1009 at), DER-330, DER-301, and DER-361, manufactured by Taguchi chemical Co., Ltd., YD8125 and YDF8170, manufactured by Nippon iron-gold chemical Co., Ltd. Examples of the phenol novolac-type epoxy resin include Epicoat152 and Epicoat154 manufactured by Mitsubishi chemical corporation, EPPN-201 manufactured by Nippon chemical corporation, and DEN-438 manufactured by Dow chemical corporation, and examples of the o-cresol novolac-type epoxy resin include EOCN-102S, EOCN-103S, EOCN-104S, EOCN-1012, EOCN-1025 and EOCN-1027 manufactured by Nippon chemical corporation, YDCN701, YDCN702, YDCN703 and YDCN704 manufactured by Nippon chemical corporation. Examples of the polyfunctional epoxy resin include Epon1031S manufactured by Mitsubishi chemical corporation, Araldite0163 manufactured by Ciba specialty Chemicals corporation, DENACOL EX-611 manufactured by NAGASECCHEMITEX corporation, EX-614B, EX-622, EX-512, EX-521, EX-421, EX-411, and EX-321. Examples of the amine-type epoxy resin include Epicoat604 manufactured by Mitsubishi chemical corporation, YH-434 manufactured by Tokyo chemical corporation, TETRAD-X and TETRAD-C manufactured by Mitsubishi gas chemical corporation, and ELM-120 manufactured by Sumitomo chemical corporation. Examples of the heterocyclic ring-containing epoxy resin include ARALDITE PT810 manufactured by Ciba specialty Chemicals, ERL4234, ERL4299, ERL4221, and ERL4206 manufactured by UCC. These epoxy resins may be used alone or in combination of 2 or more.

Additives can be added as appropriate to cure the thermosetting resin. Examples of such additives include a curing agent, a curing accelerator, and a catalyst, and when a catalyst is added, a co-catalyst can be used as needed.

When an epoxy resin is used as the thermosetting resin, an epoxy resin curing agent or a curing accelerator is preferably used, and more preferably used in combination. Examples of the curing agent include phenol resins, dicyandiamide, boron trifluoride complexes, organic hydrazide compounds, amines, polyamide resins, imidazole compounds, urea or thiourea compounds, polythiol compounds, polythioether resins having a mercapto group at the terminal, acid anhydrides, and light/ultraviolet curing agents. These may be used alone or in combination of 2 or more.

Among them, boron trifluoride-amine complexes with various amine compounds (preferably primary amine compounds) can be cited as the boron trifluoride complexes, and isophthaloyl hydrazide can be cited as the organic hydrazide compound.

Examples of the phenol resin include phenol novolac resins such as phenol novolac resin, phenol aralkyl resin, cresol novolac resin, t-butylphenol novolac resin, and nonylphenol novolac resin, resol novolac resins, and polyhydroxystyrenes such as polyparahydroxystyrene. Among them, a phenol compound having at least 2 phenolic hydroxyl groups in the molecule is preferable.

Examples of the phenol compound having at least 2 phenolic hydroxyl groups in the molecule include phenol novolac resins, cresol novolac resins, tert-butylphenol novolac resins, dicyclopentadiene cresol novolac resins, dicyclopentadiene phenol novolac resins, xylylene-modified phenol novolac resins, naphthol novolac resins, triphenol novolac resins, tetraphenol novolac resins, bisphenol a novolac resins, poly-p-vinylphenol novolac resins, and phenol aralkyl resins. Among these phenol resins, phenol novolac resins and phenol aralkyl resins are particularly preferable, and they can improve connection reliability.

Examples of the amines include chain aliphatic amines (diethylenetriamine, triethylenetetramine, hexamethylenediamine, N-dimethylpropylamine, benzyldimethylamine, 2- (dimethylamino) phenol, 2,4, 6-tris (dimethylaminomethyl) phenol, m-xylylenediamine, etc.), cyclic aliphatic amines (N-aminoethylpiperazine, bis (3-methyl-4-aminocyclohexyl) methane, bis (4-aminocyclohexyl) methane, menthenediamine, isophoronediamine, 1, 3-bis (aminomethyl) cyclohexane, etc.), heterocyclic amines (piperazine, N-dimethylpiperazine, triethylenediamine, melamine, guanamine, etc.), aromatic amines (m-phenylenediamine, 4' -diaminodiphenylmethane, diamino (Japanese: ジアミノ), etc, 4,4' -diaminodiphenyl sulfone, etc.), polyamide resins (polyamidoamine is preferred, and condensate of dimer acid and polyamine), imidazole compounds (2-phenyl-4, 5-dihydroxymethylimidazole, 2-methylimidazole, 2, 4-dimethylimidazole, 2-N-heptadecylimidazole, 1-cyanoethyl-2-undecylimidazolium-trimellitate, epoxy-imidazole adduct, etc.), urea or thiourea compounds (N, N-dialkyl urea compounds, N-dialkyl thiourea compounds, etc.), polythiol compounds, polythioether resins having a mercapto group at the terminal, acid anhydrides (e.g., tetrahydrophthalic anhydride), and light/ultraviolet curing agents (e.g., diphenyliodonium hexafluorophosphate, triphenylsulfonium hexafluorophosphate).

The curing accelerator is not particularly limited as long as it cures a thermosetting resin, and examples thereof include imidazoles, dicyandiamide derivatives, dicarboxylic dihydrazide, triphenylphosphine, tetraphenylphosphonium tetraphenylborate, 2-ethyl-4-methylimidazole-tetraphenylborate, and 1, 8-diazabicyclo [5.4.0] undecene-7-tetraphenylborate. Examples of imidazoles include imidazole, 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-ethylimidazole, 1-benzyl-2-ethyl-5-methylimidazole, 2-phenyl-4-methyl-5-hydroxydimethylimidazole, and 2-phenyl-4, 5-dihydroxymethylimidazole.

The content of the curing agent or curing accelerator for epoxy resin in the adhesive layer is not particularly limited, and the optimum content varies depending on the kind of the curing agent or curing accelerator.

The mixing ratio of the epoxy resin and the phenol resin is preferably, for example, 0.5 to 2.0 equivalents of hydroxyl group in the phenol resin per 1 equivalent of epoxy group in the epoxy resin component. More preferably 0.8 to 1.2 equivalents. That is, if the blending ratio of the two is out of the above range, the curing reaction cannot be sufficiently advanced, and the properties of the adhesive layer 3 are likely to be deteriorated. The other thermosetting resin and the curing agent are contained in an amount of 0.5 to 20 parts by mass in one embodiment and 1 to 10 parts by mass in another embodiment, based on 100 parts by mass of the thermosetting resin. The content of the curing accelerator is preferably less than the content of the curing agent, and the curing accelerator is preferably 0.001 to 1.5 parts by mass, more preferably 0.01 to 0.95 parts by mass, per 100 parts by mass of the thermosetting resin. By adjusting the amount within the above range, the progress of the sufficient curing reaction can be assisted. The content of the catalyst is preferably 0.001 to 1.5 parts by mass, and more preferably 0.01 to 1.0 part by mass, based on 100 parts by mass of the thermosetting resin.

The adhesive layer 3 of the present invention may be appropriately mixed with a filler depending on the use thereof. This can improve the cuttability of the adhesive layer 3 in an uncured state, improve handling properties, adjust melt viscosity, provide thixotropy, provide thermal conductivity to the adhesive layer 3 in a cured state, and improve adhesion.

The filler used in the present invention is preferably an inorganic filler. The inorganic filler is not particularly limited, and examples thereof include aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, aluminum nitride, aluminum borate whisker, boron nitride, crystalline silica, amorphous silica, and antimony oxide. These may be used alone or in combination of 2 or more.

Among the above inorganic fillers, alumina, aluminum nitride, boron nitride, crystalline silica, amorphous silica, and the like are preferably used from the viewpoint of improving thermal conductivity. From the viewpoint of adjustment of melt viscosity and imparting thixotropy, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, aluminum oxide, crystalline silica, amorphous silica, and the like are preferably used. In addition, alumina and silica are preferably used from the viewpoint of improving the cuttability.

When the content of the filler is 30% by mass or more, the wire-weldability is excellent. In wire bonding, the storage modulus of elasticity after curing of the adhesive layer 3 of the wire bonding die is preferably adjusted to a range of 20 to 1000MPa at 170 ℃, and when the content of the filler is 30 mass% or more, the storage modulus of elasticity after curing of the adhesive layer 3 can be easily adjusted to the range. When the content of the filler is 75% by mass or less, the adhesive layer 3 is excellent in film formability and heat fluidity during die bonding. When the heat fluidity of the adhesive layer 3 is improved at the time of die bonding, the adhesive layer 3 can be favorably adhered to the adherend, the adhesive strength can be improved, and the unevenness of the adherend can be easily embedded to suppress voids. More preferably 70% by mass or less, and still more preferably 60% by mass or less.

The adhesive layer 3 of the present invention may contain 2 or more fillers having different average particle diameters as the filler. In this case, as compared with the case of using a single filler, it is possible to easily prevent an increase in viscosity when the content ratio of the filler is high or a decrease in viscosity when the content ratio of the filler is low in the raw material mixture before the formation of a film, to easily obtain good film formability, to optimally control the fluidity of the uncured adhesive layer 3, and to obtain excellent adhesion after curing of the adhesive layer 3.

(base material tape 2)

The base tape 2 is provided for the purpose of protecting the adhesive layer 3, for the purpose of facilitating label processing for cutting the semiconductor processing tape 1 into a specific shape, and for the purpose of smoothing the adhesive layer 3. Examples of the material constituting the base tape 2 include paper, synthetic resin films such as polyethylene, polypropylene, and polyethylene terephthalate. In order to improve the releasability from the adhesive layer 3, the surface of the base tape 2 may be subjected to a release treatment such as a silicone treatment, a long-chain alkyl treatment, or a fluorine treatment as necessary. In addition, ultraviolet ray prevention treatment may be performed as necessary so that the adhesive sheet does not react with ambient ultraviolet rays. The thickness of the base tape 2 is usually 10 to 100 μm, preferably about 25 to 50 μm.

(supporting Member 15)

The support members 15 are provided on the surface of the base tape 2 opposite to the surface on which the adhesive layer 3 and the adhesive film 4 are provided, on both ends of the base tape 2 in the short-side direction, and have a thickness that is 1.0 times or more and 4.0 times or less the thickness of the adhesive layer 3 and the second adhesive layer 43. As described above, by providing the support member 15, the winding pressure applied to the semiconductor processing tape 1 is dispersed or concentrated on the support member 15 when the tape is wound into a roll, and therefore, the formation of transfer marks, which are formed by overlapping the adhesive layer 3 with the level differences between the laminated portions of the label portions 4a1 and 4a2 of the adhesive film 4 and the peripheral portion 4b of the adhesive film 4 and transferring the level differences to the surface of the flexible adhesive layer 3, can be suppressed.

The support member 15 may be provided intermittently or continuously along the longitudinal direction of the base material tape 2, but is preferably provided continuously along the longitudinal direction of the base material tape 2 from the viewpoint of more effectively suppressing the occurrence of transfer marks.

As the support member 15, for example, an adhesive tape obtained by coating an adhesive on a resin film substrate can be suitably used. The adhesive tape 1 for semiconductor processing according to the present embodiment can be formed by bonding such an adhesive tape to a predetermined position at both end portions of the base tape 2.

The base resin of the pressure-sensitive adhesive tape is not particularly limited as long as it can withstand winding pressure, and is preferably selected from the group consisting of polyethylene terephthalate (PET), polypropylene, and high-density polyethylene from the viewpoints of heat resistance, smoothness, and ease of handling.

The composition and physical properties of the adhesive for the adhesive bonding tape are not particularly limited, and the adhesive may be one that does not peel off from the base tape 2 in the winding step and storage step of the semiconductor processing tape 1.

(method of manufacturing adhesive tape for semiconductor processing 1)

Next, an example of a method for manufacturing the semiconductor processing tape 1 according to the present embodiment will be described.

First, the adhesive layer 3 is formed in a long film shape. The adhesive layer 3 can be formed by preparing a resin composition and forming it into a film by a conventional method. Specifically, for example, a method of forming the adhesive layer 3 by applying the above resin composition to an appropriate spacer (such as release paper) and drying (drying by heat treatment if necessary, such as heat curing) is exemplified. The resin composition may be a solution or a dispersion.

Next, the adhesive layer 3 is precut into the above-described planar shape using a press cutter or the like, and unnecessary portions of the periphery are peeled off and removed from the spacers, whereby a plurality of adhesive layers 3 having planar shapes are continuously formed on the long spacers. After that, the adhesive layer 3 is transferred to the long base tape 2. The adhesive layer 3 may be formed by applying a resin composition to the long base tape 2 and precutting the resin composition into a planar shape.

Further, a second adhesive layer 43 in the form of a long film is formed. The second adhesive layer 43 may be formed by preparing a resin composition and forming it into a film by a conventional method. Specifically, for example, a method of forming the second pressure-sensitive adhesive layer 43 by applying the above-mentioned resin composition to an appropriate separator (such as release paper) and drying the applied resin composition can be mentioned. The resin composition may be a solution or a dispersion.

Next, the second adhesive layer 43 is precut into the above-described planar shape using a press cutter or the like, and unnecessary portions of the periphery are peeled off and removed from the spacer, whereby a plurality of planar second adhesive layers 43 are continuously formed on the long spacer.

In addition, the first adhesive layer 42 is produced. The first pressure-sensitive adhesive layer 42 can be formed by a conventional method for forming a pressure-sensitive adhesive layer. For example, the first pressure-sensitive adhesive layer 42 can be formed on the base film 41 by a method in which the pressure-sensitive adhesive composition is applied to a predetermined surface of the base film 41, or a method in which the pressure-sensitive adhesive composition is applied to a release film (for example, a plastic film or sheet coated with a release agent) to form the first pressure-sensitive adhesive layer 42, and then the first pressure-sensitive adhesive layer 42 is transferred to a predetermined surface of the base film 41.

The substrate film 41 can be formed by a conventionally known film forming method. Examples of the film forming method include a calendering film forming method, a casting method using an organic solvent, a blow extrusion method in a closed system, a T-die extrusion method, a coextrusion method, and a dry lamination method.

Then, the first adhesive layer 42 provided on the base film 41 is laminated on the second adhesive layer 43 provided on the spacer and having a specific shape, to obtain the adhesive tape 4.

Thereafter, the spacer provided on the second adhesive layer 43 is peeled off, and the surface of the adhesive tape 4 on the second adhesive layer 43 side is bonded to the adhesive layer 3 of a specific shape provided on the base tape 2 so that the adhesive layer 3 and the center of the planar shape of the first adhesive layer 43 are aligned and laminated. In this case, the planar shape of the adhesive layer 3 is larger than the planar shape of the second adhesive layer 43, and therefore the first adhesive layer 42 comes into contact with the adhesive layer 3 and adheres to the adhesive layer at the peripheral portion of the second adhesive layer 43.

Next, the base film 41 and the first pressure-sensitive adhesive layer 42 are precut into a predetermined planar shape using a press cutter or the like, and unnecessary portions of the periphery are peeled off and removed from the base tape 2, thereby producing the tape 1 for semiconductor processing. At this time, the planar shape of the first pressure-sensitive adhesive layer 42 is larger than the planar shape of the adhesive layer 3, and therefore, the portion of the second pressure-sensitive adhesive layer 43 where the first pressure-sensitive adhesive layer 42 and the adhesive layer 3 are in contact is maintained. After that, the base material tape 2 used for the precut process may be peeled off and a known spacer may be bonded to the surface on the adhesive layer 3 side.

(method of Using adhesive tape 1 for semiconductor processing)

The semiconductor processing tape 1 is used in the following steps in the manufacturing process of a semiconductor device. As shown in fig. 3, in the semiconductor processing tape 1, a semiconductor wafer bonding step is performed in which the base tape 2 is peeled from a laminate of the adhesive layer 3, the second label portion 4a2 formed of the second adhesive layer 43, the first adhesive layer 42, and the first label portion 4a1 formed of the base film 41, and bonded to the semiconductor wafer W. More specifically, the base material tape 2 is folded back and conveyed in the peeling direction at the tip end portion of the wedge-shaped peeling member 101, so that peeling of the laminate is promoted, and only the laminate is fed forward. The semiconductor wafer W and the ring frame R are placed on the table 102 at the front lower side, and the stacked body is sent out to the upper side thereof. Further, the pressure-sensitive adhesive layer 3 is bonded to the semiconductor wafer W by providing the pressure-sensitive adhesive roller 103 above the semiconductor wafer W. Since the first pressure-sensitive adhesive layer 42 is larger than the pressure-sensitive adhesive layer 3, the first pressure-sensitive adhesive layer 42 is bonded to the ring frame R around the pressure-sensitive adhesive layer 3.

At this time, the adhesive force of the second adhesive layer 43 is small, but the planar shape of the second adhesive layer 43 is smaller than the planar shape of the adhesive layer 3, and therefore, the first adhesive layer 42 having a large adhesive force and the adhesive layer 3 are held in adhesion around the second adhesive layer 43, and therefore, the adhesive layer 3 does not float from the adhesive tape 4 even when the base tape 2 is peeled or when the one end portion of the laminate is pressed against the pressure roller 103 and the other end portion of the laminate is pulled in the peeling direction of the base tape 2 to apply a tensile force to the laminate.

Next, as shown in fig. 4, the ring frame R is fixed to a cutting device not shown. At this time, the semiconductor wafer W faces upward, and the semiconductor processing tape 1 faces downward. Then, as shown in fig. 5, a dicing process is performed on the semiconductor wafer W. Specifically, first, the semiconductor processing tape 1 is suction-supported from the base film 41 surface side by the suction table 105. Then, the semiconductor wafer W and the adhesive layer 3 are cut into units of semiconductor chips C by the dicing blade 104 and the units are diced into individual pieces. When the second pressure-sensitive adhesive layer 43 is a radiation-curable pressure-sensitive adhesive, the adhesive strength is reduced by irradiating the lower surface side of the base film 41 with radiation to cure the second pressure-sensitive adhesive layer 43.

Thereafter, as shown in fig. 6, an expanding step of stretching the adhesive tape 4 holding the diced semiconductor chip C and the adhesive layer 3 in the outer circumferential direction of the ring frame R is performed. Specifically, the adhesive tape 4 holding the plurality of cut semiconductor chips C and the adhesive layer 3 is lifted from the lower surface side of the adhesive tape 4 by the hollow cylindrical push-up member 106, and the adhesive tape 4 is stretched in the outer circumferential direction of the ring frame R.

After the expanding step, as shown in fig. 7, a picking-up step of picking up the semiconductor chip C with the adhesive tape 4 in an expanded state is performed. Specifically, the semiconductor chip C is pushed up by the needle bar 107 from the lower surface side of the adhesive tape 4 and sucked by the suction jig 108, whereby the individual semiconductor chips C are picked up with the adhesive layer 3. At this time, since the adhesive force of the second adhesive layer 43 is small, the semiconductor chip C and the adhesive layer 3 are easily peeled off from the second adhesive layer 43, and the semiconductor chip C can be picked up well.

Then, after the pickup step is performed, the bonding step is performed. Specifically, the adhesive layer 3 side that accompanies the picking up of the semiconductor chip C in the picking up step is disposed at the bonding position of the substrate such as the lead frame or the package substrate. Then, the adhesive layer 3 is subjected to a heat treatment at a temperature of 150 to 350 ℃, whereby the semiconductor chip C and the substrate are mechanically bonded. The bonding step may be performed under a non-pressurized condition, or may be performed under a pressurized condition.

Then, a wire bonding step is performed to electrically connect the tip of the terminal portion of the substrate and the electrode pad on the semiconductor chip C by a bonding wire. Next, a sealing step of sealing the semiconductor chip C with a sealing resin is performed to complete the semiconductor device.

(examples)

Next, the present invention will be described in more detail based on examples. The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

[ base film A ]

As the substrate film, HIMILAN AM-7316 (trade name, manufactured by Mitsui DuPont chemical Co., Ltd.) which is an ethylene-methacrylic acid- (2-methyl-propyl acrylate) 3-membered copolymer-Zn + + -ionomer resin was used to prepare a film having a thickness of 90 μm. One side of the film was subjected to corona treatment to obtain a base film.

[ adhesive composition A for first adhesive layer ]

An adhesive composition a of the first adhesive layer was prepared by dissolving 5 parts by mass of a curing agent (trade name "L-45E", product of seiko chemical corporation) in ethyl acetate and stirring the solution per 100 parts by mass of an acrylic adhesive (trade name "SG-50Y", product of seiko chemical corporation).

[ adhesive composition A for second adhesive layer ]

2.3 parts by mass of a curing agent (product name "L-45E" manufactured by Sudoku Chemicals Co., Ltd.) and 7 parts by mass of a polyisocyanate composition (product name "TKA-100" manufactured by Asahi Kasei Chemicals Co., Ltd.) were dissolved in ethyl acetate and stirred with respect to 100 parts by mass of an acrylic adhesive (product name "AP-FE 2503" manufactured by Xinzhou village chemical industries, Ltd.) to prepare an adhesive composition A of the second adhesive layer.

[ adhesive composition B for second adhesive layer ]

1.7 parts by mass of a curing agent (product name "L-45E" manufactured by Sudoku chemical industries Co., Ltd.) and 3.9 parts by mass of a polyisocyanate composition (product name "TKA-100" manufactured by Asahi Kasei Chemicals Co., Ltd.) were dissolved in ethyl acetate and stirred with respect to 100 parts by mass of an acrylic adhesive (product name "AP-FE 2503" manufactured by Xinzhongcun chemical industries Co., Ltd.) to prepare an adhesive composition B of the second adhesive layer.

[ adhesive composition C for second adhesive layer ]

0.34 parts by mass of a curing agent (product name "L-45E" manufactured by Sudoku chemical industries Co., Ltd.) and 1.1 parts by mass of a polyisocyanate composition (product name "TKA-100" manufactured by Asahi Kasei Chemicals Co., Ltd.) were dissolved in ethyl acetate and stirred with respect to 100 parts by mass of an acrylic adhesive (product name "AP-FE 2503" manufactured by Xinzhongcun chemical industries Co., Ltd.) to prepare an adhesive composition C of the second adhesive layer.

[ adhesive composition D for second adhesive layer ]

2.8 parts by mass of a curing agent (product name "L-45E" manufactured by Sudoku chemical industries Co., Ltd.) and 8.4 parts by mass of a polyisocyanate composition (product name "TKA-100" manufactured by Asahi Kasei Chemicals Co., Ltd.) were dissolved in ethyl acetate and stirred with respect to 100 parts by mass of an acrylic adhesive (product name "AP-FE 2503" manufactured by Xinzhongcun chemical industries Co., Ltd.) to prepare an adhesive composition D of the second adhesive layer.

[ adhesive composition E for second adhesive layer ]

0.5 part by mass of a curing agent (product name "L-45E" manufactured by Soken chemical Co., Ltd.) was dissolved in ethyl acetate and stirred with respect to 100 parts by mass of an acrylic pressure-sensitive adhesive (product name "AP-FE 2503" manufactured by Ningmura chemical industries, Ltd.) to prepare a pressure-sensitive adhesive composition E of the second pressure-sensitive adhesive layer.

[ adhesive composition A ]

To a composition comprising 50 parts by mass of an epoxy resin (trade name "1002" manufactured by Mitsubishi chemical corporation), 100 parts by mass of an epoxy resin (trade name "806" manufactured by Mitsubishi chemical corporation), 5 parts by mass of a curing agent (trade name "Dyhard (registered trade name) 100 SF" manufactured by Evonik Degussa), 150 parts by mass of a silica filler (trade name "SO-C2" manufactured by ADMAFINE corporation) and 5 parts by mass of a silica filler (trade name "AEROSIL R972" manufactured by Japan AEROSIL corporation), MEK was added, and the mixture was stirred and mixed to prepare a uniform composition.

To this, 100 parts by mass of a phenoxy resin (product name "PKHH" manufactured by Gabriel Phenoxies Co., Ltd.), 0.4 part by mass of a coupling agent (product name "KBM-802" manufactured by shin-Etsu SILICONE Co., Ltd.) and 0.5 part by mass of a curing accelerator (product name "Curezol 2 PHZ-PW" manufactured by Siguo Kagaku Kogyo Co., Ltd.) were added and mixed with stirring until uniform. The obtained product was filtered through a 100-mesh filter and subjected to vacuum degassing to obtain a varnish of the adhesive composition c-1A.

< example 1>

The adhesive composition a of the first adhesive layer was applied to a separator made of a long polyethylene terephthalate film after release treatment so that the thickness after drying became 5 μm, and after drying at 110 ℃ for 3 minutes, the adhesive composition a was bonded to a base film a to produce an adhesive sheet a having a first adhesive layer formed on the base film a.

Next, the pressure-sensitive adhesive composition a of the second pressure-sensitive adhesive layer was applied to the separator made of a cut sheet-like polyethylene terephthalate film after the release treatment so that the thickness after drying became 10 μm, dried at 110 ℃ for 3 minutes, and then bonded to the polyethylene terephthalate film after the release treatment, to prepare a plurality of pressure-sensitive adhesive sheets B having the second pressure-sensitive adhesive layer formed on the polyethylene terephthalate film.

Further, an adhesive composition a was applied to a base tape made of a long polyethylene terephthalate film after release treatment so that the thickness after drying became 30 μm, and the tape was dried at 110 ℃ for 5 minutes to prepare an adhesive film having an adhesive layer formed on the polyethylene terephthalate film. Thereafter, the adhesive layer was cut into a circular shape having a diameter of 320mm, and a spacer made of a long polyethylene terephthalate film subjected to mold release treatment was attached to the adhesive layer-side surface.

Next, the second adhesive layer of the adhesive sheet B was cut into a circular shape having a diameter of 308 mm. Then, the polyethylene terephthalate film was peeled off from the adhesive sheet a, a plurality of second adhesive layers of the adhesive sheet B were laminated at equal intervals on the exposed first adhesive layer, and a separator made of a long polyethylene terephthalate film after release treatment was laminated on the surface on the second adhesive layer side again to obtain an adhesive tape.

Next, the spacer made of the polyethylene terephthalate film was peeled off from the adhesive film, and the polyethylene terephthalate film of the adhesive tape was peeled off, and the center of the exposed second adhesive layer was laminated so as to overlap the center of the adhesive layer.

Thereafter, the base film and the first adhesive layer were cut into a circular shape having a diameter of 370mm, to prepare a sample of the semiconductor processing tape of example 1.

< example 2>

A sample of the semiconductor processing tape of example 2 was produced in the same manner as in example 1, except that the adhesive composition B of the second adhesive layer was used instead of the adhesive composition a of the second adhesive layer.

< example 3>

A sample of the semiconductor processing tape of example 3 was produced in the same manner as in example 1, except that the adhesive composition C of the second adhesive layer was used instead of the adhesive composition a of the second adhesive layer.

< example 4>

A sample of the semiconductor processing tape of example 4 was produced in the same manner as in example 1, except that the adhesive composition D of the second adhesive layer was used instead of the adhesive composition a of the second adhesive layer.

< example 5>

A sample of the semiconductor processing tape of example 5 was produced in the same manner as in example 1, except that the adhesive composition E of the second adhesive layer was used instead of the adhesive composition a of the second adhesive layer.

< example 6>

A sample of the semiconductor processing tape of example 6 was produced in the same manner as in example 2, except that the second adhesive layer of the adhesive sheet B was cut into a circular shape having a diameter of 290 mm.

< comparative example 1>

A sample of the semiconductor processing tape of comparative example 1 was produced in the same manner as in example 1, except that the second adhesive layer of the adhesive sheet B was cut into a circular shape having a diameter of 321 mm.

< comparative example 2>

A sample of the semiconductor processing tape of comparative example 2 was produced in the same manner as in example 2, except that the second adhesive layer of the adhesive sheet B was cut into a circular shape having a diameter of 321 mm.

< comparative example 3>

A sample of the semiconductor processing tape of comparative example 3 was produced in the same manner as in example 3, except that the second adhesive layer of the adhesive sheet B was cut into a circular shape having a diameter of 321 mm.

< comparative example 4>

A sample of the semiconductor processing tape of comparative example 4 was produced in the same manner as in example 4, except that the second adhesive layer of the adhesive sheet B was cut into a circular shape having a diameter of 321 mm.

< comparative example 5>

A sample of the semiconductor processing tape of comparative example 5 was produced in the same manner as in example 5, except that the second adhesive layer of the adhesive sheet B was cut into a circular shape having a diameter of 321 mm.

< comparative example 6>

The adhesive composition B of the second adhesive layer was applied to a separator made of a long polyethylene terephthalate film after release treatment so that the thickness after drying was 15 μm, and after drying at 110 ℃ for 3 minutes, the adhesive composition B was bonded to the base film a to produce an adhesive sheet C having the second adhesive layer formed on the base film a.

Further, an adhesive composition a was applied to a base tape comprising a long polyethylene terephthalate film after release treatment so that the thickness after drying became 30 μm, and the tape was dried at 110 ℃ for 5 minutes to prepare an adhesive film having an adhesive layer formed on the polyethylene terephthalate film. Thereafter, the adhesive layer was cut into a circular shape having a diameter of 320mm, and a spacer made of a long polyethylene terephthalate film subjected to mold release treatment was attached to the adhesive layer-side surface.

Thereafter, the base film and the second adhesive layer were cut into a circular shape having a diameter of 370mm, to prepare a sample of the semiconductor processing tape of comparative example 6.

The semiconductor processing tapes obtained in the above examples and comparative examples were evaluated as follows. The evaluation results are shown in table 1.

[ measurement of SUS surface peeling force ]

From each of the adhesive sheets a used in the tapes for semiconductor processing of examples 1 to 5 and comparative examples 1 to 5, 3 test pieces 25mm wide × 300mm long were taken, polyethylene terephthalate films were peeled off, and these were bonded to SUS304 steel plates 1.5mm to 2.0mm thick as defined in JIS G4305 finished with water-resistant abrasive paper No. 280 as defined in JIS R6253, and then 2kg rubber rolls were pressed and pressed 3 times back and forth, and left for 1 hour, and then the adhesive force of the first adhesive layer was measured using a tensile tester suitable for JIS B7721 in which the measured value fell within a range of 15 to 85% of the capacity thereof. The measurement was carried out by a 180 ℃ exfoliation method, at which the drawing speed was 300 mm/min. The measurement temperature was 23 ℃ and the measurement humidity was 50%. The second pressure-sensitive adhesive layer of each pressure-sensitive adhesive sheet B was bonded to the first pressure-sensitive adhesive layer exposed by peeling the polyethylene terephthalate film from the pressure-sensitive adhesive sheet a, 3 test pieces 25mm wide by 300mm long were taken, the polyethylene terephthalate film was peeled from the second pressure-sensitive adhesive layer, and the adhesive strength of the second pressure-sensitive adhesive layer was measured in the same manner as described above. Further, 3 test pieces of 25mm wide by 300mm long were taken from the pressure-sensitive adhesive sheet C, and the polyethylene terephthalate film was peeled from the second pressure-sensitive adhesive layer, and the adhesive force of the second pressure-sensitive adhesive layer was measured in the same manner as described above.

[ evaluation of peeling of adhesive layer ]

The base material tapes were peeled from the semiconductor processing tapes of examples and comparative examples using a bonding apparatus (trade name: DFM2700, manufactured by Disco Co.), and silicon wafers having a thickness of 100 μm and a diameter of 300mm were bonded to the exposed adhesive layers. The semiconductor processing tapes of examples and comparative examples, to which the silicon wafer was bonded, were checked for the presence or absence of peeling of the adhesive layer. The silicon wafer was evaluated as good, and good was evaluated as "o", and when the adhesive layer was peeled from the adhesive tape during the adhesion to the silicon wafer, the silicon wafer was evaluated as bad, and good was evaluated as "x".

[ evaluation of pickup Property ]

The semiconductor processing tapes of the examples and comparative examples bonded to the silicon wafer were subjected to a pick-up test using a chip sorter (trade name: CAP-300II, manufactured by Canon machine) by preparing a tape obtained by cutting the silicon wafer and the adhesive layer into a size of 15mm × 15mm and a tape obtained by cutting the silicon wafer and the adhesive layer into a size of 0.5mm × 0.5mm, respectively, using a cutting device (DFD 6340, manufactured by Disco).

The pickup conditions are as follows.

Cut into 0.5mm squares

The shape of the push-up pin is as follows: radius of 0.45mm, front end curvature radius R0.15 mm

Stitch pushing-up height: 50 μm

The pushing-up speed of the pins: 10mm/sec

Vacuum cup (Japanese: コレット) shape: 0.4mm □

The amount of expansion: 10mm

A ring frame: model DTF-2-6-1 manufactured by DISCO Inc. (SUS420J 2)

Cut into 15mm squares

The shape of the push-up pin is as follows: radius of 0.45mm, front end curvature radius R0.35 mm

Stitch pushing-up height: 350 μm

The pushing-up speed of the pins: 10mm/sec

The shape of the vacuum sucker is as follows: 14mm □

The amount of expansion: 10mm

A ring frame: model DTF-2-6-1 manufactured by DISCO Inc. (SUS420J 2)

The chips diced under the above conditions were picked up by 50 chips, and whether the picking was successful or not was confirmed. Good chips were evaluated as good when all chips were picked up at both 15mm square and 0.5mm square, and 1 or more chips were left on the adhesive layer at15 mm square and could not be picked up, however, the chip pickup was performed for all chips at 0.5mm square, and evaluated as "Δ" as a permissible product, and even 1 chip at both 15mm square and 0.5mm square was left on the adhesive layer and could not be picked up, but the non-pickable chips are only chips located at a portion corresponding to a portion where the second adhesive layer is not present in the peripheral portion of the silicon wafer, any chip located outside the peripheral edge portion was picked up, and evaluated as a permissible product as "Δ", and even 1 chip remained on the adhesive layer and was not picked up in both the 15mm square and the 0.5mm square, as "x".

[ evaluation of chip fly-off ]

In the pickup evaluation test, the presence or absence of chip scattering was visually checked. The chips scattered at both the 15mm square and the 0.5mm square were evaluated as good chips, the chips scattered at 0.5mm square as 1 or more, but the chips scattered at15 mm square as acceptable chips, and the chips scattered at both the 15mm square and the 0.5mm square as "x".

[ evaluation of Ring frame peeling ]

The semiconductor processing tapes of examples and comparative examples, which were subjected to the pick-up evaluation test, were checked for the presence of peeling from the ring frame. The one not peeled from the ring frame was evaluated as "good", the one peeled at a position less than 1/4 in the portion bonded to the ring frame was evaluated as "Δ" as an acceptable product, and the one peeled at a position equal to or more than 1/4 in the portion bonded to the ring frame in the adhesive tape was evaluated as "poor".

[ Table 1]

As shown in table 1, in the semiconductor processing tapes of examples 1 to 6, the adhesive force of the first adhesive layer was larger than that of the second adhesive layer, the planar shape of the first adhesive layer was larger than that of the adhesive layer, and the first adhesive layer was in contact with the adhesive layer in the peripheral portion of the second adhesive layer, and therefore, favorable results were obtained in both the ring frame peeling evaluation and the adhesive layer peeling evaluation. Further, the adhesive tapes for semiconductor processing of examples 1 to 3 had good results in the pickup evaluation and the chip scattering evaluation, because the adhesive force between the second adhesive layer and the surface of SUS304 was 0.1 to 0.6N/25mm and the adhesive force between the first adhesive layer and the surface of SUS304 was 1 to 10N/25mm under the conditions of the peel angle of 180 degrees and the peel speed of 300mm/min at 23 ℃ and 50% RH. In the semiconductor processing tape of example 4, the adhesive strength between the second adhesive layer and the SUS304 surface was less than 0.1N/25mm, and therefore, in the case of a chip having a square of 0.5mm, the chip was scattered, but the allowable range was reached. In the tape for semiconductor processing of example 5, the adhesive strength between the second adhesive layer and the SUS304 surface exceeded 0.6N/25mm, and therefore, a pickup failure occurred in the case of a chip of 15mm square, but the adhesive strength was within the allowable range. In the semiconductor processing tape of example 6, the diameter of the second adhesive layer was equal to or smaller than the diameter of the silicon wafer, and all chips located outside the peripheral edge portion of the silicon wafer could be picked up, but pickup failure occurred in the chips located at the portion corresponding to the portion where the second adhesive layer was not present in the peripheral edge portion.

In the semiconductor processing tapes of comparative examples 1 to 5, the planar shape of the second pressure-sensitive adhesive layer was larger than that of the adhesive layer, and therefore, poor results were obtained in the evaluation of peeling of the adhesive layer. In addition, since the first pressure-sensitive adhesive layer having a higher adhesive force than the second pressure-sensitive adhesive layer was not provided in the semiconductor processing tape of comparative example 6, a difference was produced between the ring frame peeling evaluation and the adhesive layer peeling evaluation.

Description of the reference numerals

1: adhesive tape for semiconductor processing

2: substrate adhesive tape

3: adhesive layer

4: adhesive tape

41: substrate film

42: first adhesive layer

43: second adhesive layer

15: supporting member

W: semiconductor wafer

R: ring frame

C: semiconductor chip

Claims

1. An adhesive tape for semiconductor processing, characterized in that,

a base material film, a first adhesive layer and a second adhesive layer are sequentially arranged,

an adhesive layer is provided on a surface of the second adhesive layer opposite to the base film and the first adhesive layer,

the first adhesive layer has an adhesive force greater than that of the second adhesive layer,

the first adhesive layer, the second adhesive layer, and the adhesive layer each have a planar shape,

the planar shape of the adhesive layer is larger than that of the second adhesive layer, the planar shape of the first adhesive layer is larger than that of the adhesive layer,

the first adhesive layer is in contact with the adhesive layer in a peripheral portion of the second adhesive layer.

2. The adhesive tape for semiconductor processing according to claim 1,

the adhesive force between the second adhesive layer and the SUS304 surface is 0.1N/25 mm-0.6N/25 mm under the conditions of 23 ℃ and 50% RH, the peeling angle is 180 degrees, and the peeling speed is 300 mm/min.

3. The adhesive tape for semiconductor processing according to claim 1 or 2,

the adhesive force between the first adhesive layer and the SUS304 surface is 1N/25 mm-10N/25 mm under the conditions of 23 ℃ and 50% RH, the peeling angle is 180 degrees, and the peeling speed is 300 mm/min.

4. The adhesive tape for semiconductor processing according to any one of claims 1 to 3,

the first pressure-sensitive adhesive layer is a radiation non-curable type that is not cured by irradiation with radiation.

5. The adhesive tape for semiconductor processing according to any one of claims 1 to 4,

the second pressure-sensitive adhesive layer is a radiation non-curable type that is not cured by irradiation with radiation.

6. The adhesive tape for semiconductor processing according to any one of claims 1 to 5,

the planar shape of the second adhesive layer is larger than that of the semiconductor wafer bonded to the adhesive layer.